Your absolute refusal to be defeated is so impressive. It was so enlightening to go on this epic journey with you. You have such a gift to explain exactly what you're doing and why you're doing it that way. I feel like I'm actually participating in finding the solution right there along side you. I felt victorious when you found the answer as if I had found it myself. Your critical thinking skills and logic are amazing. My hat is off to you!
On a DMM, the resistance measurement and the diode measurement work the same way: Meter applies a current through the component-under-test, and measures the resulting voltage across it. In resistance mode, the meter calculates and displays R = V/I. In diode mode, the meter simply displays the voltage. On different resistance ranges, the meter selects a different current to apply, so that the resulting voltage is in a tractable range. (While the DMM is attempting to apply a precise fixed current, it only has a limited range of max voltage that it can apply that current at.) For diode mode, my Fluke 187 applies 1mA. (You can measure this on a second meter, or apply diode mode to a 1k resistor and see resulting voltage reading.) That's enough current to read a voltage that's representative of the diode nominal forward voltage, for signal diodes and relatively small power diodes. It's also much lower than what would harm an LED, no series resistor needed. In fact a series resistor would cause the meter's voltage reading to be increased by the resistor voltage drop, so not terribly helpful. Additional side point: For either measurement, but notably for resistance, the meter has to measure a voltage. It assumes that voltage is a result of the current that it applied, and can thus calculate a legit resistance. However, if there's any other electrical activity in the component under test (eg: it's in some larger circuit that's operating, or has partially charged capacitors), then the voltage measured by the meter will not be just related to the current it applied, and hence the resistance displayed will be wrong, possibly wildly so.
I have a very similar problem with my wife's car we have a 2000 slk 230 witch we have owned for 17 years it recently developed a battery drain 3 days and it wouldn't start I checked all the fuses and only found one with any current flow of 530mAmps which I found to be the air pump in the boot. I fitted a new one and thought fine but the battery is still draining so I looked at all the fuses again and only found one fuse with a 20mA drain but I found a 100Mamp drain on the pos battery cable to the alternator and also a 50mA drain on the pos cable to the crash separater relay also 80MA on the negative battery cable if I disconnect the negative cable I still have 120ma on the battery to alternator and 10ma to the crash separater I have done a diode test at the alternator and have 814mvolts also done a ac voltage test at the alternator was 415mvolts any help is appreciated..
Congratulations. Epic hunt down. With out getting into the painful details you helped me solve a no start problem on one of my engines on my SeaRay 340 with twin 8.1 Mercruisers. I had spent weeks trying to determine the problem and had run out of resources on the boat forums when I started looking at some of the car forums for some clues. I came across your channel and one of your videos led me to the answer. I now watch your channel regularly. Thank You
this was my EURIKA post. There are seven pages of the saga if you are interested in following the hunt on the Searay forum... Update...Final update , I hope... The port engine is running. Quite nicely. After spending all Sunday doing a pin out and not finding any shorts or bad grounds or broken wires , I was feeling defeated. If you remember , I had determined there was a no spark condition. I came to this conclusion after removing a spark plug from each cylinder bank and grounding it and cranking the engine. No spark. Not even a weak spark. Also the spark plugs are relatively new with about 30 hours on them. Also , it would not fire on ether. That sent me delving into all possibilities for a no spark condition. When I ran out of ideas and the boat forums were not providing any answers , I began researching car forums. A lot of very technical diagnosis videos on youtube. Shrodingers Box was particularity helpful. It got me thinking of the veracity of my spark check. I bought a spark tester and put it on the previously dead spark plug cylinders and low and behold...spark. Long story short, there were 5 dead spark plugs. How that is even remotely possible , I do not know. The engine ran perfectly when put away for winter and somehow those spark plugs decided to fail just sitting there. I feel somewhat foolish for spending the last 3 weeks killing myself chasing down this problem and it turning out to be the simple spark plug but the evidence really wasn't leading me to mass spark plug suicide. Anyway , I bought 8 AC 41-983 plugs , installed them , and the engine fired right up. It quit after 30 seconds and I did a fuel rail bleed and all was well. By the way , I have read that these engines are fussy with plugs and to only use the AC plugs. That was what I did have installed before the problem. So there you have it. I will be taking the boat out hopefully tomorrow to run her through the paces and confirm this nightmare is over. Thanks to all for the help/suggestions and I hope this thread may help someone else in the future.@@SchrodingersBox
I've learned through my experience troubleshooting that intermittents can be found with a heat gun or freeze spray (compressed air upside down). Typically it's a bad solder joint in those cases, and those stressors can help show it through expansion and contraction. Good troubleshooting! I too am not a fan of under dashboard work. When it looks like it's going to be a very long time, I'll do all kinds of contorting and in the extreme cases, will rip the seat out to allow me to get in there.
Great video. I've got a couple of headaches in the shop right now. You spend two days on diag and get paid for... But, I own a shop and I do those for my customers. Also, I fix cars. Money is not everything. The satisfaction of figuring things out is priceless. P.S. I know you dont work as a mechanic, but your'e better than 95% of the techs out there.
The alternator would read infinity if it was just a three phase generator with six backwards connected diodes. A car alternator is a bit more complicated. It has a coil producing a variable magnetic field, controlled by a signal from the ECU or within the alternator. The current to the coil is large, producing a strong magnetic field, when much charging current is needed and low or off when little or no charging current is needed. You might read a part of this circuit while the diodes are "off" (reverse biased). Think of a simple bike generator that could be controlled by using weak or strong permanent magnets. This is why you don't need to "take the car to the highway for an hour" to charge the battery. You can have it sit in idle, the generator will be controlled to charge the battery even then. I do like how you clearly say when you talk about stuff that's uncharted terrain. For me, it's just the other way round. I am an electronics circuit designer but know little about cars and still learn a lot while fixing them. To me, a car is an electrical circuit with this weird combustion engine in the middle, being surrounded by sensors and controlled by a computer ;-)
Hahaha great perspective and analogy!!! Yeah I have a friend who is an electronics guy and he says the same thing. Understands everything clearly- even the PCM programming and networks. But the engine-- blah. lol!!
Nice find Matt! I knew you'd find it! I am retired now but 40+ years of bending over hoods, trunks, etc & contorting under dashes I don't blame you. I still have a blower motor on one of my vehicles that you have to literally cut out and then install plates on the new motor to reinstall thanks to GM engineers that don't have to channge them. I am milking it out until it just fails. Making a little noise but if I turn the radio up you don't hear it.😂 Again nice diagnosis Matt!!
Another great video, the 0.835V is the forward conduction voltage for the rectifier. Normally 0.7v depending upon the current flow but can be as low as 0.3,depending upon substrate type.
@@SchrodingersBox It can be tough to diagnose a full wave bridge rectifier set up in car alternators without tearing it apart. You really need a scope to measure the amount of AC ripple that still exists on the output.
Well done tracking the parasitic draw to the steering control module not going to sleep. However, given the message is "message not received from ECM", how certain can one be that it's the EPS that's failing to hear the message, and not the ECM failing to send the message? That said, I guess the underlying problem could be the EPS failing to detect power down and continuing to expect ECM messages when there aren't any because ECM is powered down, or some such. I wonder if the EPS detects power down with a sense wire that's broken.
yeah I am not sure the specifics of how that works. I believe when a module powers down. it sends a message to the ECM- my friend Chad covered this in a video a couple years back we did together. not seeing that power down message would cause this code. conversely- modules also regularly send little “hey I’m here… hey I’m here… hey I’m here” signals to let the PCM know they are alive but the way this code reads it sounds more like the former.
@@SchrodingersBox the steering module is possibly confused as to why its on, but the other module isn't talking to it. Probably a symptom rather than the cause of the issue.
@@SchrodingersBox I looked at the EPS portion of the schematic for Gen 4 and Gen 5 Elantra, and see that it has connections B+, B-, CANHi, CANLo, and IGN. So it should be able to tell from IGN that the car is OFF, and thus not be waiting for CAN messages. It would be most interesting to see if indeed that IGN wire is low when this problem occurs. I mean, we know that module is so convenient to access! 🙂
If what happens in the garage doesn't stay in the garage I'd be in prison. They don't look kindly on keeping hostages or using metric wrenches on American cars.
21:43 Diode mode readings in both directions are because of the VOLRAGE REGULATOR. Remove the VR and you will then see readings in only one direction ... or at least you should if diodes are all good.
I agree it's certainly scientific to test diodes with the DVOM but it's just not practical for most as it'd require opening the alternator to test properly. Great stuff!
1. Alternator, 2. Audio system, 3. Light staying on, 4. Central locking system. These are the most common causes of unauthorised current draw. Now I haven't watched all the videos, so I don't know what has been checked and what hasn't. But a question I would insert here is,why did the car lock itself? No-one told it to lock.
Nice. I know those Hyundais have a plastic/rubber coupling/ pushing the customer should think about replacing at the same time if the column has to come out anyway.
I had similar problem with the mother in laws car but like you I am to old and the car is 22 years old so I just fitted a remote battery disconnect lol. cheating I know but the module would have been more than the car is worth
when sitting still ignition on running and not running turn steering wheel left and right if you hear a noise and have a small amount of play in the steering wheel. there is a small looks like rubber bushing kinda like what is used in a love-joy coupling kinda shaped like a starr have replaced several at the dealership price used to be $1.00 Dorman was $20.00 yes the dealer was cheaper the loose play throws a code can't remember but keeps it from true center but the code well just can't remember what it was. but was real easy to repair the motor bolts on with i think 3 fasteners and was easy. book says remove column but you can easily reach up there and replace. might not be the issue.
Glad you think so. Yes the deduction is essential to help rule out things so you don’t go down rabbit holes. It just about killed me to deduce the BCM cannot possibly be the cause- especially with red flags all over it, but math is math -- well at least it still is. Biology used to be biology but not anymore lol.
Part 5? Update from customer possibly? Also I was curious if it would have been possible to temporarily remote wire that module on top of the fuse panel so you could get to the fuses under it? Could a possible temp quick fix be pulling the fuse for that power steering module? Would the car be drivable without it until a permanent fix? Also Excellent content! Thanks.
I will give an update for sure but I am never doing another “typical day in the garage” video again hahahahaha. The last two series I ran into these huge mysterious electrical issue.
Still going thru process of elimination with my 2006 Subaru sti po302. Going to check for vacuum leak later today wit my autool sdt 206 smoke machine ,then going to swap injectors
Wait-- why would you swap injectors AND check for a vacuum leak?? Why not determine if it’s a vacuum leak or a fuel issue first and just do the necessary tests?
Hi Matt. Thanks a lot for all the info you provide for us. Usually, how much do you charge a customer for the diagnosis, and is it rated by HOURS or not? I live in a country where most of customer do not appreciate that sometimes they should pay more to get good diagnosis rather than replacing thousands of part & modules by gust guessing. Also, lets assume that after three days, you couldn't fix this car; would you still charge the customer full ammount? If not, what would you do?
I used to not charge for diagnostic. Now I charge $100 flat rate. If I solve it in 5 minutes, $100. If it takes me 3 hours, $100. But also I will add on if any labor for removing parts etc is involved- for example if I have to remove the starter to get to a crankshaft sensor I charge the labor rate for a starter R+R
Let's hope the customer can tell you what the solution was when they get it fixed. And let's hope it won't be "shop replaced ECM, EPS, ... for thousands of dollars and error is still present" and it's back in your garage 👀👀
Yeah that would suck however the EPS will fix it for sure. Now if the shop claims any other things as well- then that would be a problem with them and the shop. I will follow up!!
For what it's worth, a quick scan around the car's interior with your IR camera, when you first confirmed the presence of the parasitic draw, might have been a good investment of a couple of minutes. 12 volts at 500 mA is 6 watts. A module dissipating this amount of power might well show up!
Great diagnosis! One question for curiosity, is it possible the EPS module is staying powered on due to a fault at ignition switch? Not sure how command to turn on is fed to this module, so my question may be nonsense. I also couldn't track whether this issue would occur only after a key on/off action, or if it would pop up randomly after a period of vehicle being powered off.
Good question but no- if that was the case other modules would be turned on as well. It fused directly from the 80A breaker so if was on from ignition switch, essentially so would everything else be on.
This was one of the most frustrating ones I have ever endured but man I was so happy to see that amp draw!!!! The cold, the inconsistency, the endless variables. This was super satisfying.
You kept me riveted to my iPad for this series. I’m stunned there were no trolls in the comments saying I told you so. You taught me a bunch. Thanks. Is this the first diagnosis with no trolls?
Hahahahaha great observation and in fact this was intentionally designed as a “troll test”. If you notice- I only gave the data between episodes but still didn’t know what the issue was. I specifically asked at the end of one episode “I believe I see clues to the issue- if you agree tell me in the comments!!” Only a couple of people out of thousands who watched gave their thoughts, and even then not a single one said “check the power steering module”. Not a one. In fact one person gave a wrong answer and later deleted their comment hahahahaha. Now had I not done that, then as usual I would surely have had dozens if not hundreds of “well I would have tested the power steering module first”. I have other videos in the past where I have done this same experiment and it’s 100% reproducible. They always respond after the fact but never when you proactively call them out for opinions.
Question , could the can timeout code have been set, because the ps module stayed awake, and no modules are talking to it, because they all went to sleep?
Oh that’s a good point. It could be that too. If I wanted I could have tapped into the CAN network and see evidence for that by transcoding the signals during this issue.
Hahahahaha totally!!! I have no idea what that dude is talking about lol. Reminds me of the guy in the movie “Pooty Tang” (one of the greatest movies ever made). “Wadda ta my damie… wadda ta”.
Did the customer get the fault fixed? Did it solve the parasitic drain issue? It would be nice to get a bit of closure if possible. Not criticising you, but just asking if it all worked out in the end.
@SchrodingersBox - Thank you for that. It's much appreciated. Being on the Autistic Spectrum leaves me kind of upset without closure. It's like a mystery film ending without the final revelation scenes. Anyway, thank you for the update and also for your entire channel.
Hahahahahaha!!! Yeah. Yeah it does. Man this was such a challenge and the freezing weather was literally painful. My fingers were so numb at times I couldn’t even use the computer lol. I’m flying high now though!!!
Intermittent faults like this are the worst, and we usually end up short changing ourselves. It becomes a stubborn matter of not wanting to be defeated and you end up putting countless hours into it but you struggle to actually charge the customer for all those hours so you kind of need to take the victory of conquering it as part of the payment lol
Well said. To be honest if I hadn’t already committed to the videos on this I would have returned it to the customer hahahaha. But with thousands of people waiting to see what it is, I just can’t up and quit due to stress. Like a female Olympian lol.
What are your thoughts on battery unhooking and welding? I never have unhooked one and weld on em all the time. I also only ground onto what I am welding. If broken exhaust manifold bolt I make sure its right on the head. Exhaust I grind a clean spot for the exact pipe im welding on not the other side of the flange. I always said that if the "battery acts as a sponge" for the alternator why wouldn't it for the welder?
I also have a newer inverter mig welder and not a old transformer ac stick welder. They do say if you operate any machine wrong enough it can turn into a smoke machine.
I so so seldom do any welding but when I have, sometimes I have unhooked the battery and other times I forgot to do so and I never damaged anything. I agree- I don’t understand how it would cause any damage honestly. I don’t even think the battery is what “absorbs” the energy- it seems to me it routes right back through the welder.
Exactly what I think. Iv unhooked a few but havent for a few years. I mean Im sure not everyone practices good grounding and thats what happens. Those pixies traven in circles what goes in must come out. Im sure there is a way to get a load in between and thats the issue.
If only you could've been a 20-something year old guy so that we could've seen the definitive repair. Unfortunately the Wisdom and Agility slopes go in opposite directions on the age graph 😭 great series either way, thanks for the entertainment.
Hahahaha yeah true. But honestly even so- filming it would be a total nightmare. It would be impossible to show what I am doing anyway. I’m happy with this. It’s 100% confirmed the module. .65A on the module power wire- that’s it. Done.
We had 6 degrees this morning. Brrrr. Makes a fella want to stay inside and abandon the garage. But hey we mechanics are a stubborn bunch ain't we. Thanks for Brrrrrringing us along. Keep the coffee hot, thanks.
I installed a battery switch on the negative terminal of my daughters car so she can depend on the car I need some time with the car to track down the draw in it The switch is also helpful for testing purposes as it is an old fashioned blade switch I can clip one side of my ammeter to the 2 sides of the blade, then open it flowing through the meter and you don’t interrupt the power to wake everything
Hey Matt nice intro Parasite drains take patients You held in there May I add my 2 cents Using the DVOM In diode mode on the generator you got reading both ways because each stator windings has a positive and negative diode connected in Series most not all have six diodes divided into 3 legs among the 3 stator windings.You were correct.I see diodes using electron flow -- electrons current flowing against the arrow makes it easier to see electrons entering the negative post charging the battery putting the acid content in the electrolyte solution CHEERS All that really matters that the electrons know what to do ,it’s about the amps.
Hey Matt Got 2 possible answers 1 stator winding open and 2 the DVOM diode test can’t see the diode because it takes 0.6 volts to turn it on to much voltage drop@@SchrodingersBox
@@SchrodingersBox Also bear in mind an alternator is 3 sub-components - 3phase generator (3 coils probably with 1 end of each connected to ground - sorry GROUND!!!!). Then a 3 phase bridge rectifier - 3 pairs of diodes in series/parallel (plenty of diagrams on google), and then finally a voltage regulator (probably controlled by the ECU via PWM) that smooths out the voltage ripple and gives you a steady and accurate charging voltage no matter what RPM the alternator is doing. At some point I guess the diodes and/or regulator might be replaced by a switch mode PSU like on a computer, and at that point all hope of testing would go out the window. So on a car alternator you won't have direct access to the diode terminals. On a motorbike this is separated with the generator is inside the engine casing with a regulator/rectifier somewhere else where it can be cooled in the airflow. These can then be disconnected so you can meter out the diodes. I think Suzuki workshop manuals or the Honda Common Service manual are normally quite at documenting this with resistance tests and expected values. So your Ripple test is probably a good way to go (I did the same test yesterday on a CCTV system with dodgy picture quality - saved me having to buy and rewire a 16 way PSU). You could also use your clamp meter round the alternator to battery cable when the vehicle is off to see if there is any current flow through the alternator.
Oh man you have no idea. It’s not just the persistent victory, but enduring the frigid cold, the frustration with my electronics not working in the cold, my fingers getting numb, the hours and hours of editing the video-- yeah this was one of my more epic victories IMO.
Your absolute refusal to be defeated is so impressive. It was so enlightening to go on this epic journey with you. You have such a gift to explain exactly what you're doing and why you're doing it that way. I feel like I'm actually participating in finding the solution right there along side you. I felt victorious when you found the answer as if I had found it myself. Your critical thinking skills and logic are amazing. My hat is off to you!
Oh wow man, made my day!!! Thanks!!!
On a DMM, the resistance measurement and the diode measurement work the same way: Meter applies a current through the component-under-test, and measures the resulting voltage across it. In resistance mode, the meter calculates and displays R = V/I. In diode mode, the meter simply displays the voltage. On different resistance ranges, the meter selects a different current to apply, so that the resulting voltage is in a tractable range. (While the DMM is attempting to apply a precise fixed current, it only has a limited range of max voltage that it can apply that current at.)
For diode mode, my Fluke 187 applies 1mA. (You can measure this on a second meter, or apply diode mode to a 1k resistor and see resulting voltage reading.) That's enough current to read a voltage that's representative of the diode nominal forward voltage, for signal diodes and relatively small power diodes. It's also much lower than what would harm an LED, no series resistor needed. In fact a series resistor would cause the meter's voltage reading to be increased by the resistor voltage drop, so not terribly helpful.
Additional side point: For either measurement, but notably for resistance, the meter has to measure a voltage. It assumes that voltage is a result of the current that it applied, and can thus calculate a legit resistance. However, if there's any other electrical activity in the component under test (eg: it's in some larger circuit that's operating, or has partially charged capacitors), then the voltage measured by the meter will not be just related to the current it applied, and hence the resistance displayed will be wrong, possibly wildly so.
Thanks for the great explanation!!
Thanks for the great explanation!!
I have a very similar problem with my wife's car we have a 2000 slk 230 witch we have owned for 17 years it recently developed a battery drain 3 days and it wouldn't start I checked all the fuses and only found one with any current flow of 530mAmps which I found to be the air pump in the boot. I fitted a new one and thought fine but the battery is still draining so I looked at all the fuses again and only found one fuse with a 20mA drain but I found a 100Mamp drain on the pos battery cable to the alternator and also a 50mA drain on the pos cable to the crash separater relay also 80MA on the negative battery cable if I disconnect the negative cable I still have 120ma on the battery to alternator and 10ma to the crash separater I have done a diode test at the alternator and have 814mvolts also done a ac voltage test at the alternator was 415mvolts any help is appreciated..
Congratulations. Epic hunt down.
With out getting into the painful details you helped me solve a no start problem on one of my engines on my SeaRay 340 with twin 8.1 Mercruisers. I had spent weeks trying to determine the problem and had run out of resources on the boat forums when I started looking at some of the car forums for some clues. I came across your channel and one of your videos led me to the answer. I now watch your channel regularly.
Thank You
Oh wow- I actually wouldn’t mind hearing a few of the details!
Matt has videos containing valuable information. He helped me come to understand fuel trims back when I owned my Trans Am many years ago.
Oh holy cow hey Glycerin, great to see you!!
this was my EURIKA post. There are seven pages of the saga if you are interested in following the hunt on the Searay forum...
Update...Final update , I hope...
The port engine is running. Quite nicely. After spending all Sunday doing a pin out and not finding any shorts or bad grounds or broken wires , I was feeling defeated.
If you remember , I had determined there was a no spark condition. I came to this conclusion after removing a spark plug from each cylinder bank and grounding it and cranking the engine. No spark. Not even a weak spark. Also the spark plugs are relatively new with about 30 hours on them. Also , it would not fire on ether. That sent me delving into all possibilities for a no spark condition. When I ran out of ideas and the boat forums were not providing any answers , I began researching car forums. A lot of very technical diagnosis videos on youtube. Shrodingers Box was particularity helpful.
It got me thinking of the veracity of my spark check. I bought a spark tester and put it on the previously dead spark plug cylinders and low and behold...spark. Long story short, there were 5 dead spark plugs. How that is even remotely possible , I do not know. The engine ran perfectly when put away for winter and somehow those spark plugs decided to fail just sitting there. I feel somewhat foolish for spending the last 3 weeks killing myself chasing down this problem and it turning out to be the simple spark plug but the evidence really wasn't leading me to mass spark plug suicide.
Anyway , I bought 8 AC 41-983 plugs , installed them , and the engine fired right up. It quit after 30 seconds and I did a fuel rail bleed and all was well. By the way , I have read that these engines are fussy with plugs and to only use the AC plugs. That was what I did have installed before the problem.
So there you have it. I will be taking the boat out hopefully tomorrow to run her through the paces and confirm this nightmare is over. Thanks to all for the help/suggestions and I hope this thread may help someone else in the future.@@SchrodingersBox
Excellent series of video’s, great deduction and zero’d in on the fault - intermittent faults are the worst
Thanks really glad you enjoyed it. This was quite an experience lol
I've learned through my experience troubleshooting that intermittents can be found with a heat gun or freeze spray (compressed air upside down). Typically it's a bad solder joint in those cases, and those stressors can help show it through expansion and contraction.
Good troubleshooting! I too am not a fan of under dashboard work. When it looks like it's going to be a very long time, I'll do all kinds of contorting and in the extreme cases, will rip the seat out to allow me to get in there.
Great video. I've got a couple of headaches in the shop right now. You spend two days on diag and get paid for... But, I own a shop and I do those for my customers. Also, I fix cars. Money is not everything. The satisfaction of figuring things out is priceless. P.S. I know you dont work as a mechanic, but your'e better than 95% of the techs out there.
Oh wow thanks for the compliment!!
The alternator would read infinity if it was just a three phase generator with six backwards connected diodes. A car alternator is a bit more complicated. It has a coil producing a variable magnetic field, controlled by a signal from the ECU or within the alternator. The current to the coil is large, producing a strong magnetic field, when much charging current is needed and low or off when little or no charging current is needed. You might read a part of this circuit while the diodes are "off" (reverse biased).
Think of a simple bike generator that could be controlled by using weak or strong permanent magnets.
This is why you don't need to "take the car to the highway for an hour" to charge the battery. You can have it sit in idle, the generator will be controlled to charge the battery even then.
I do like how you clearly say when you talk about stuff that's uncharted terrain. For me, it's just the other way round. I am an electronics circuit designer but know little about cars and still learn a lot while fixing them. To me, a car is an electrical circuit with this weird combustion engine in the middle, being surrounded by sensors and controlled by a computer ;-)
Hahaha great perspective and analogy!!! Yeah I have a friend who is an electronics guy and he says the same thing. Understands everything clearly- even the PCM programming and networks. But the engine-- blah. lol!!
Nice find Matt! I knew you'd find it! I am retired now but 40+ years of bending over hoods, trunks, etc & contorting under dashes I don't blame you. I still have a blower motor on one of my vehicles that you have to literally cut out and then install plates on the new motor to reinstall thanks to GM engineers that don't have to channge them. I am milking it out until it just fails. Making a little noise but if I turn the radio up you don't hear it.😂 Again nice diagnosis Matt!!
Thanks brother!! Yeah if I did dashboard work I’d be in a wheelchair lol.
Sounds like a Suburban or Tahoe.
Another great video, the 0.835V is the forward conduction voltage for the rectifier. Normally 0.7v depending upon the current flow but can be as low as 0.3,depending upon substrate type.
Well dang that sounds even more useless as a diagnostic hahahaha. If it has a 300% range of error I am just going to ripple it.
@@SchrodingersBox It can be tough to diagnose a full wave bridge rectifier set up in car alternators without tearing it apart. You really need a scope to measure the amount of AC ripple that still exists on the output.
Well done tracking the parasitic draw to the steering control module not going to sleep. However, given the message is "message not received from ECM", how certain can one be that it's the EPS that's failing to hear the message, and not the ECM failing to send the message? That said, I guess the underlying problem could be the EPS failing to detect power down and continuing to expect ECM messages when there aren't any because ECM is powered down, or some such. I wonder if the EPS detects power down with a sense wire that's broken.
yeah I am not sure the specifics of how that works. I believe when a module powers down. it sends a message to the ECM- my friend Chad covered this in a video a couple years back we did together. not seeing that power down message would cause this code.
conversely- modules also regularly send little “hey I’m here… hey I’m here… hey I’m here” signals to let the PCM know they are alive but the way this code reads it sounds more like the former.
@@SchrodingersBox the steering module is possibly confused as to why its on, but the other module isn't talking to it. Probably a symptom rather than the cause of the issue.
Could be. In either case we know where to focus.
@@SchrodingersBox I looked at the EPS portion of the schematic for Gen 4 and Gen 5 Elantra, and see that it has connections B+, B-, CANHi, CANLo, and IGN. So it should be able to tell from IGN that the car is OFF, and thus not be waiting for CAN messages. It would be most interesting to see if indeed that IGN wire is low when this problem occurs. I mean, we know that module is so convenient to access! 🙂
If what happens in the garage doesn't stay in the garage I'd be in prison.
They don't look kindly on keeping hostages or using metric wrenches on American cars.
21:43 Diode mode readings in both directions are because of the VOLRAGE REGULATOR. Remove the VR and you will then see readings in only one direction ... or at least you should if diodes are all good.
I agree it's certainly scientific to test diodes with the DVOM but it's just not practical for most as it'd require opening the alternator to test properly. Great stuff!
1. Alternator, 2. Audio system, 3. Light staying on, 4. Central locking system. These are the most common causes of unauthorised current draw. Now I haven't watched all the videos, so I don't know what has been checked and what hasn't. But a question I would insert here is,why did the car lock itself? No-one told it to lock.
Nice. I know those Hyundais have a plastic/rubber coupling/ pushing the customer should think about replacing at the same time if the column has to come out anyway.
17:20 If you see positrons flowing through the alternator I think you have some much bigger problems! :-) But the gist of the point is valid.
2:00 The prices on the sign in back of you needs to be modified (:
Hahaha for sure!!!
Using God’s news, swearword is a very professional. I do enjoy your content.
I had similar problem with the mother in laws car but like you I am to old and the car is 22 years old so I just fitted a remote battery disconnect lol. cheating I know but the module would have been more than the car is worth
when sitting still ignition on running and not running turn steering wheel left and right if you hear a noise and have a small amount of play in the steering wheel. there is a small looks like rubber bushing kinda like what is used in a love-joy coupling kinda shaped like a starr have replaced several at the dealership price used to be $1.00 Dorman was $20.00 yes the dealer was cheaper the loose play throws a code can't remember but keeps it from true center but the code well just can't remember what it was. but was real easy to repair the motor bolts on with i think 3 fasteners and was easy. book says remove column but you can easily reach up there and replace. might not be the issue.
Very educational and worth watching the deduction method. Thanx!
Glad you think so. Yes the deduction is essential to help rule out things so you don’t go down rabbit holes. It just about killed me to deduce the BCM cannot possibly be the cause- especially with red flags all over it, but math is math -- well at least it still is. Biology used to be biology but not anymore lol.
Part 5? Update from customer possibly? Also I was curious if it would have been possible to temporarily remote wire that module on top of the fuse panel so you could get to the fuses under it? Could a possible temp quick fix be pulling the fuse for that power steering module? Would the car be drivable without it until a permanent fix? Also Excellent content! Thanks.
I will give an update for sure but I am never doing another “typical day in the garage” video again hahahahaha. The last two series
I ran into these huge mysterious electrical issue.
By the way 🙂, if you're going to call a DMM a "DVOM", then really you have to call it a "DVOAFHzVd+M" or something hahaha.
Hahaha yes I even mentioned this in a video before in fact lol. I’m just going to call it an LGBTQIA+ and then no one will dare argue lol.
Loving these typical weekends in garage videos. Love to see more
Still going thru process of elimination with my 2006 Subaru sti po302. Going to check for vacuum leak later today wit my autool sdt 206 smoke machine ,then going to swap injectors
Wait-- why would you swap injectors AND check for a vacuum leak?? Why not determine if it’s a vacuum leak or a fuel issue first and just do the necessary tests?
Hi Matt. Thanks a lot for all the info you provide for us.
Usually, how much do you charge a customer for the diagnosis, and is it rated by HOURS or not?
I live in a country where most of customer do not appreciate that sometimes they should pay more to get good diagnosis rather than replacing thousands of part & modules by gust guessing.
Also, lets assume that after three days, you couldn't fix this car; would you still charge the customer full ammount? If not, what would you do?
I used to not charge for diagnostic. Now I charge $100 flat rate. If I solve it in 5 minutes, $100. If it takes me 3 hours, $100. But also I will add on if any labor for removing parts etc is involved- for example if I have to remove the starter to get to a crankshaft sensor I charge the labor rate for a starter R+R
This was like watching prison break.... couldn't stop watching 😂. That how I dive into things sadly
Hahahaha oh man I lost soooooo much sleep watching that series hahahah!!!!
“Just one more episode and then I’m going to bed”…. 5 times. Hahahaha.
Let's hope the customer can tell you what the solution was when they get it fixed. And let's hope it won't be "shop replaced ECM, EPS, ... for thousands of dollars and error is still present" and it's back in your garage 👀👀
Yeah that would suck however the EPS will fix it for sure. Now if the shop claims any other things as well- then that would be a problem with them and the shop. I will follow up!!
For what it's worth, a quick scan around the car's interior with your IR camera, when you first confirmed the presence of the parasitic draw, might have been a good investment of a couple of minutes. 12 volts at 500 mA is 6 watts. A module dissipating this amount of power might well show up!
Yep I did that- found nothing. Always easier to look back on it though. If only I had crawled up under the dash and looked at the EPS the first time!
Great diagnosis! One question for curiosity, is it possible the EPS module is staying powered on due to a fault at ignition switch? Not sure how command to turn on is fed to this module, so my question may be nonsense. I also couldn't track whether this issue would occur only after a key on/off action, or if it would pop up randomly after a period of vehicle being powered off.
Good question but no- if that was the case other modules would be turned on as well. It fused directly from the 80A breaker so if was on from ignition switch, essentially so would everything else be on.
Awesome troubleshooting Matt.Powerful use of thermal imaging.
Man that thermal imager is one the best values I ever saw. I am going to have to thank that company that sent it to me.
I just found out I got unsubscibed from your channel. I haven't seen your videos for a awhile.
Welcome back!!! I bet you will see things have changed quite a bit!!! Hopefully for the better!
Sweet! Nice job in finding this. I think your perseverance and enthusiasm led to a great video series on this vehicle. Thank you for doing it!
This was one of the most frustrating ones I have ever endured but man I was so happy to see that amp draw!!!! The cold, the inconsistency, the endless variables. This was super satisfying.
Bernie ,,?? Ms Vikki and her Kayy. 😀😀😀
You kept me riveted to my iPad for this series. I’m stunned there were no trolls in the comments saying I told you so. You taught me a bunch. Thanks. Is this the first diagnosis with no trolls?
Hahahahaha great observation and in fact this was intentionally designed as a “troll test”.
If you notice- I only gave the data between episodes but still didn’t know what the issue was. I specifically asked at the end of one episode “I believe I see clues to the issue- if you agree tell me in the comments!!” Only a couple of people out of thousands who watched gave their thoughts, and even then not a single one said “check the power steering module”. Not a one. In fact one person gave a wrong answer and later deleted their comment hahahahaha.
Now had I not done that, then as usual I would surely have had dozens if not hundreds of “well I would have tested the power steering module first”.
I have other videos in the past where I have done this same experiment and it’s 100% reproducible. They always respond after the fact but never when you proactively call them out for opinions.
So.
Does the power steering still work if the ECM loses comms. with the steering module?
Yes the power steering worked perfectly fine. It simply wouldn’t shut off sometimes.
Bernie ,,?? Ms Vikki and her Kayy. 😀😀😀
dude you are so mysterious lol.
@@SchrodingersBox go to bed?? Dansher nerds you fresh tomorrow
Oh it's an X Ray machine. Watch y voltages. 🙂
So strange. But intriguing…
Oh i am here for this! Thank You .
Glad to have you! I dont think you will be disappointed.
You got us all near the end with the to be continued next week 😂 was nearly cursing u
Hahahahahaha!!!!! It worked!!!!!!
Question , could the can timeout code have been set, because the ps module stayed awake, and no modules are talking to it, because they all went to sleep?
Oh that’s a good point. It could be that too. If I wanted I could have tapped into the CAN network and see evidence for that by transcoding the signals during this issue.
Please don't start the engine and shut it off continuously shut it off like it's not good for the because of the low oil pressure from it not running
That’s why on the first start I let it run over 5 seconds- until oil pressure showed. After that the engine is primed, it doesn’t matter then.
Bernie ,?! Me Vikki and her Kayy. 😀
Just say no to drugs 👁️
Hahahahaha totally!!! I have no idea what that dude is talking about lol. Reminds me of the guy in the movie “Pooty Tang” (one of the greatest movies ever made).
“Wadda ta my damie… wadda ta”.
@@SchrodingersBox right 😂😂 missed his meds . Iam guessing lithium
Did the customer get the fault fixed? Did it solve the parasitic drain issue?
It would be nice to get a bit of closure if possible. Not criticising you, but just asking if it all worked out in the end.
Hahaha yes customer had the module replaced and parasitic drawn is gone!!
@SchrodingersBox - Thank you for that. It's much appreciated.
Being on the Autistic Spectrum leaves me kind of upset without closure. It's like a mystery film ending without the final revelation scenes.
Anyway, thank you for the update and also for your entire channel.
&@$#%!!! You got it!! Don't it feel great to be a gangster?
Hahahahahaha!!! Yeah. Yeah it does. Man this was such a challenge and the freezing weather was literally painful. My fingers were so numb at times I couldn’t even use the computer lol. I’m flying high now though!!!
these kinds of anomolies are infuriating.... code writers need to be better at catching/throwing these errors...
Wouldn't extreme cold and heat affect the alternator diodes?
I am sure there must be some impact as temperature always has some impact on resistance.
the gadgets channel has a data logger you can connect to cell phone and log drains over night ivan uses one on his channel they are great and cheap
Oh that’s good to know!! That’s what I essentially did with my laptop but the cold weather seemed to make it unreliable.
Intermittent faults like this are the worst, and we usually end up short changing ourselves. It becomes a stubborn matter of not wanting to be defeated and you end up putting countless hours into it but you struggle to actually charge the customer for all those hours so you kind of need to take the victory of conquering it as part of the payment lol
Well said. To be honest if I hadn’t already committed to the videos on this I would have returned it to the customer hahahaha. But with thousands of people waiting to see what it is, I just can’t up and quit due to stress. Like a female Olympian lol.
@@SchrodingersBox lol yup spot on
What are your thoughts on battery unhooking and welding? I never have unhooked one and weld on em all the time. I also only ground onto what I am welding. If broken exhaust manifold bolt I make sure its right on the head. Exhaust I grind a clean spot for the exact pipe im welding on not the other side of the flange. I always said that if the "battery acts as a sponge" for the alternator why wouldn't it for the welder?
I also have a newer inverter mig welder and not a old transformer ac stick welder. They do say if you operate any machine wrong enough it can turn into a smoke machine.
I so so seldom do any welding but when I have, sometimes I have unhooked the battery and other times I forgot to do so and I never damaged anything. I agree- I don’t understand how it would cause any damage honestly. I don’t even think the battery is what “absorbs” the energy- it seems to me it routes right back through the welder.
Exactly what I think. Iv unhooked a few but havent for a few years. I mean Im sure not everyone practices good grounding and thats what happens. Those pixies traven in circles what goes in must come out. Im sure there is a way to get a load in between and thats the issue.
Great feeling to finally find the issue.
Omg you wouldn’t believe it. This was soooo frustrating especially with the extreme cold. I honestly was about to give up man.
If only you could've been a 20-something year old guy so that we could've seen the definitive repair. Unfortunately the Wisdom and Agility slopes go in opposite directions on the age graph 😭 great series either way, thanks for the entertainment.
Hahahaha yeah true. But honestly even so- filming it would be a total nightmare. It would be impossible to show what I am doing anyway.
I’m happy with this. It’s 100% confirmed the module. .65A on the module power wire- that’s it. Done.
I just would like to say I am learning a lot from your videos and sure do appreciate them keep them coming. From Kurdistan, Iraq.
I appreciate that!! Wow I didn’t know I had any viewers all the way from Iraq!!! Amazing!!
You sure the diode reading in the "wrong" direction is not due to tunnelling? :)
Not familiar with tunneling. Whats that?
@@SchrodingersBox breaking through the reverse bias of the diode, I think.
Good job 👍
For the algorithm
How did ur phone show the temperature?
Its a coffee cup with a temp sensor in it google "EMBER"
We had 6 degrees this morning. Brrrr. Makes a fella want to stay inside and abandon the garage. But hey we mechanics are a stubborn bunch ain't we. Thanks for Brrrrrringing us along. Keep the coffee hot, thanks.
Oh man today felt like summer by comparison. It was actually legitimately painful those first 3 episodes!
Maybe put a trickle charger on when they park for a time. That way, any current drain would be replaced, just a slight inconvenience...
good idea- but then how would they know if the condition was happening if car started right up because it was always charged?
I installed a battery switch on the negative terminal of my daughters car so she can depend on the car I need some time with the car to track down the draw in it
The switch is also helpful for testing purposes as it is an old fashioned blade switch I can clip one side of my ammeter to the 2 sides of the blade, then open it flowing through the meter and you don’t interrupt the power to wake everything
that was a good one.
Glad you agree!! I thought so too!!
I'm an electrician, but I absolutely hate troubleshooting car electrical problems. Well done.
Hahaha the car’s owner told me same thing. He actually did the air conditioning in my garage! But he won’t touch a cars electrical lol.
I always worked on ac electrical stuff too, it seems simpler cuz the induction always present in the wires - dc power stuff is way more complicated
Hey Matt nice intro Parasite drains take patients You held in there May I add my 2 cents Using the DVOM In diode mode on the generator you got reading both ways because each stator windings has a positive and negative diode connected in Series most not all have six diodes divided into 3 legs among the 3 stator windings.You were correct.I see diodes using electron flow -- electrons current flowing against the arrow makes it easier to see electrons entering the negative post charging the battery putting the acid content in the electrolyte solution CHEERS All that really matters that the electrons know what to do ,it’s about the amps.
ohhhhhhh thanks for the explanation!!! so how did others get the “reading or no reading” result then???
Hey Matt Got 2 possible answers 1 stator winding open and 2 the DVOM diode test can’t see the diode because it takes 0.6 volts to turn it on to much voltage drop@@SchrodingersBox
@@SchrodingersBox Also bear in mind an alternator is 3 sub-components - 3phase generator (3 coils probably with 1 end of each connected to ground - sorry GROUND!!!!). Then a 3 phase bridge rectifier - 3 pairs of diodes in series/parallel (plenty of diagrams on google), and then finally a voltage regulator (probably controlled by the ECU via PWM) that smooths out the voltage ripple and gives you a steady and accurate charging voltage no matter what RPM the alternator is doing. At some point I guess the diodes and/or regulator might be replaced by a switch mode PSU like on a computer, and at that point all hope of testing would go out the window.
So on a car alternator you won't have direct access to the diode terminals. On a motorbike this is separated with the generator is inside the engine casing with a regulator/rectifier somewhere else where it can be cooled in the airflow. These can then be disconnected so you can meter out the diodes. I think Suzuki workshop manuals or the Honda Common Service manual are normally quite at documenting this with resistance tests and expected values.
So your Ripple test is probably a good way to go (I did the same test yesterday on a CCTV system with dodgy picture quality - saved me having to buy and rewire a 16 way PSU). You could also use your clamp meter round the alternator to battery cable when the vehicle is off to see if there is any current flow through the alternator.
That's what I call heroic persistence, and the victory must have been all the more sweet for that!
Oh man you have no idea. It’s not just the persistent victory, but enduring the frigid cold, the frustration with my electronics not working in the cold, my fingers getting numb, the hours and hours of editing the video-- yeah this was one of my more epic victories IMO.
It was the combination of the severe cold and the technical challenge, which made it so impressive.
Great trouble shooting video. These types if problems are the most difficult for mechanics.
👏👏👏👏
Thank you!! Very proud of this one!!