A very precise and detailed explanation, thank you for deciding to share your experience. I am happy that there is still someone who also thinks about beginners. Thank you very much
i have a question. my car ONLY when the weather is freezing. on the initial start up in morning . the car does not high idle . it idle at 1000 aka it shakes . it suppose to idle at 1800 or more. the car has an electronic TB no IAC. i checked the coolant temp sensor value in morning it matches with the air temp sensor .what could be the problem in your opinion
Amazing! Another great video for beginners and advanced technicians! Keep up the great work! I may have to enroll to your classes for a refreshment soon!
The only thing that doesn’t make sense to me is at 10:00 (signal short to ground) and low voltage reading. I’m not good with electronics generally, but I would have thought it would be a 5V (high voltage) scenario because the signal wire is sending out 5V and the ground side remains at 0. I’m probably confusing things but if you put multimeter probes on the end of the signal wire just before the short, and the other side (ground side), wouldn’t that be a 5V difference? Or are you effectively testing ground to ground because of the short to ground and therefore 0 V?
You are testing a wire that has become a ground, the entire wire from the sensor to the PCM is now being grounded. The resistor inside the PCM is now the only resistor in the circuit and will use all the voltage. The PCM sensing unit is measuring the voltage after the resistor.
Great video please keep them coming. Old school technician . Can you do some on pull up and pull down circuits and the difference in ground side switched and positive side switch. Little lost. Thanks
To add to MrDiagnosTech's answer. The only time you will see a voltage drop across any resistor or any load is when current is flowing. Remember this "NO CURRENT FLOW = NO VOLTAGE DROP"
This is a great job here. Please, I need your opinion on a BMW i'm working on. The issue is, at high temp, even above 120°C, the fan will not start(that is abnormal). Once you unplug the ects, the fan will come up(normal, showing an open circuit). The confusing part is that, there is no DTC and all measurements are ok. What is your take on this?
@@Jemimah-b1y I would do a voltage drop test from the sensor signal to DME and from the sensor ground to a known good ground. It might have unwanted resistance on the circuit.
@MRDIAGNOSTECH Thanks, i've done all of these tests. the resistance on the signal wire is around 42ohms and sensor ground 18ohms, which I feel is a normal wire resistance. I began to suspect the DME, i changed the DME, but it was the same(fan not coming on). I tried to on the AC to observe if there would be a difference, NO! Just thinking, can a bad thermostat sensor be a cause?
@MRDIAGNOSTECH woke up to see your response. Your responses are really insightful and helpful. Yeah, voltage drop btw sensor signal and Dme is 0.098v. with the ects unplugged, a measure btw the sensor signal wire and a good ground should give a 4.9v - 5.1v and a measure btw sensor ground and bat+ should give battery voltage(BMW manual) and that is what i'm getting. With the sensor plugged, i measure btw sensor signal(back probed), and ground gives 2.6v after an overnight sleep test. Pls where am i getting it wrong?
@@Jemimah-b1y You should be doing oil changes and changing brakes. You shouldn't be working on electrical systems because you lack the basic electrical knowledge. Go to school, read some books, or take online classes.
There are 2 types of thermistors: 1. NTC (Negative Temperature Coefficient) - Resistance decreases as temperature increases. 2. PTC (Positive Temperature Coefficient) - Resistance increases as temperature increases. The ECT (Engine Coolant Temperature) sensor is a NTC thermistor.
Amazing video. Thank you for being the ONLY one on UA-cam to actually discuss the theory, provide ALL the details, and demonstrate!
A very precise and detailed explanation, thank you for deciding to share your experience. I am happy that there is still someone who also thinks about beginners. Thank you very much
You're very welcome!
@@MRDIAGNOSTECH yes good explanation.
i have a question. my car ONLY when the weather is freezing. on the initial start up in morning . the car does not high idle . it idle at 1000 aka it shakes . it suppose to idle at 1800 or more. the car has an electronic TB no IAC. i checked the coolant temp sensor value in morning it matches with the air temp sensor .what could be the problem in your opinion
You have a hell of a way of teaching. Thank you and keep up the good work
Very, very good explanation
this gives you confidence
Many Thanks
DomIJ.
Amazing! Another great video for beginners and advanced technicians! Keep up the great work! I may have to enroll to your classes for a refreshment soon!
I love this lesson.please can you do one video for 3 wire sensors.
Very good teaching 👍🏻
Awesome just the problem I needed explained,thanks so much great explanation 😂
awesome excellent diagnose thanks
What a great explanation. Thanks for sharing.
The only thing that doesn’t make sense to me is at 10:00 (signal short to ground) and low voltage reading. I’m not good with electronics generally, but I would have thought it would be a 5V (high voltage) scenario because the signal wire is sending out 5V and the ground side remains at 0. I’m probably confusing things but if you put multimeter probes on the end of the signal wire just before the short, and the other side (ground side), wouldn’t that be a 5V difference? Or are you effectively testing ground to ground because of the short to ground and therefore 0 V?
You are testing a wire that has become a ground, the entire wire from the sensor to the PCM is now being grounded. The resistor inside the PCM is now the only resistor in the circuit and will use all the voltage. The PCM sensing unit is measuring the voltage after the resistor.
Very informative Video. Keep it Up ❤❤🎉
Brilliant video.
Could you do one on the camshaft sensor.
Good refresher course 👍🏽
Yes, thanks
The best explanation I've seen on UA-cam. Thank you.
Great video, many thanks for posting
Great information. Thank you 🙏🙏
Thank you for sharing your knowledge
Great job thank you for the help
Thanks for explanation, well done
thank you!!! great Job!!!
One of the best explanations Greetings from Germany😊
Thanks! 😃
Thank you sir very very good explanation
Great video please keep them coming. Old school technician . Can you do some on pull up and pull down circuits and the difference in ground side switched and positive side switch. Little lost. Thanks
Nice 👍🏼 ! 🔥 🧰
Thanks mate !
Very good job! Why doesn't the resistor inside the PCM create a voltage drop? Why, after that resistance, is the voltage still 5 volts?
When it is unplugged, the circuit is incomplete, and voltage is not used.
Thanks! 🙏
To add to MrDiagnosTech's answer. The only time you will see a voltage drop across any resistor or any load is when current is flowing. Remember this "NO CURRENT FLOW = NO VOLTAGE DROP"
Useful
This is a great job here. Please, I need your opinion on a BMW i'm working on. The issue is, at high temp, even above 120°C, the fan will not start(that is abnormal). Once you unplug the ects, the fan will come up(normal, showing an open circuit). The confusing part is that, there is no DTC and all measurements are ok. What is your take on this?
@@Jemimah-b1y I would do a voltage drop test from the sensor signal to DME and from the sensor ground to a known good ground. It might have unwanted resistance on the circuit.
@MRDIAGNOSTECH Thanks, i've done all of these tests. the resistance on the signal wire is around 42ohms and sensor ground 18ohms, which I feel is a normal wire resistance. I began to suspect the DME, i changed the DME, but it was the same(fan not coming on). I tried to on the AC to observe if there would be a difference, NO! Just thinking, can a bad thermostat sensor be a cause?
@@Jemimah-b1y voltage drop using volts, not ohms. It should not exceed 0.100V.
@MRDIAGNOSTECH woke up to see your response. Your responses are really insightful and helpful. Yeah, voltage drop btw sensor signal and Dme is 0.098v. with the ects unplugged, a measure btw the sensor signal wire and a good ground should give a 4.9v - 5.1v and a measure btw sensor ground and bat+ should give battery voltage(BMW manual) and that is what i'm getting. With the sensor plugged, i measure btw sensor signal(back probed), and ground gives 2.6v after an overnight sleep test. Pls where am i getting it wrong?
@@Jemimah-b1y You should be doing oil changes and changing brakes. You shouldn't be working on electrical systems because you lack the basic electrical knowledge. Go to school, read some books, or take online classes.
What if you are getting 5v on the signal wire as well the ground wire at point B6. How do you fix that?
You have problems in sensor ground in PCM
You can try with a wire from B6 to (B-)=ground
Or from A=ECT to (B-)=ground
❤❤❤❤❤❤
So usually heat creates resistance which lowers voltage. Here resistance drops and so does voltage.
@@Outrunninaround. That's because this is a negative coefficient temperature sensor.
That's a NTC sensor
There is PTC sensor too
There are 2 types of thermistors:
1. NTC (Negative Temperature Coefficient) - Resistance decreases as temperature increases.
2. PTC (Positive Temperature Coefficient) - Resistance increases as temperature increases.
The ECT (Engine Coolant Temperature) sensor is a NTC thermistor.
GREAT VIDEO!!