dude this helps so much! I did a 4.8 to 5.3 swap on my truck and couldn't figure out why the ECM from the 5.3 truck wasn't working haha. (donor truck is identical to swap truck in every way except it had a 5.3 instead of a 4.8)
I had this issue once, reprogrammed the key to the truck no problem. Happened again a few days later. Then again. And finally I took it to the dealership. They wanna replace the passlock sensor for $968!
I had a 2003 Tahoe LT auto ride. It had all-wheel drive leather DVD player 5.3 l pretty much every feature and yet it was only a regular Tahoe. A pretty rare truck. You'd even had DVD player. Like I said, it was actually more loaded than my current O2 Denali which I love
When I was young my dad had a square body but then he had a GMT 400 and then he ended up trading that in and getting an 800. I spent a lot of years behind that 800 dashboard and now I drive one. Myself and my children sit behind an 800 dashboard
I got 02 Denali pretty sure it's been bypassed and the air ride system definitely been bypassed. Couple other things too for sure. She's an old family hauler still hauling future GMT 800 Lovers
A company in Florida makes a bypass for the air rides. It goes on the computer in cargo area. Also theres a module under the spare tire. It rots along withe the tire carrier. Causes no starts and service suspensions light s. Cut brown and brown/ white stripe and tie together. Fixes the ride contteol light
I've heard you can put four-wheel drive transfer case in an Escalade or Denali and make it four-wheel drive well actually it will be two-wheel drive or all-wheel drive. Not four wheeler. But still that would be cool. It will shave gas, be able to do burnouts and less wear and tear on the components cuz the all-wheel drive heats up suspension and steering components
The security system will never shut the engine down while driving. That would be a safety issue. If the system fails while driving the message will come on but continue to run until its shut off. So if you have a stall concern while driving its not the security system that caused the stall
@@MattsShop That would be a module failed and caused stall and during the failure it lost the passcode for security system. Root cause wasnt the security system. Start a vehicle and while its running unplug the passlock sensor. It will continue to run and the security light will come on.
I have vats problems . Wires were loose in the black clip the red yellow and black wires run to on top of the barrel. Di they sell new connectors and wiring for that?
My 99 chevy express..5.7..i replaced the pcm 4 years ago..run great...for a while now my engne will start, die etc.then would start, run good...the other day my battery went dead from headlighrs left on...now the engen starts and dies...im wondering if it needs a 30 min reboot?
Hey matt can you please explain the cold start on this engines that knocks for about 2 minutes and then goes away? I been trying to figured out but it looks like you know a lot about this engines
Piston slap is what I've been told. Pistons need to heat up and expand to take up the piston to cylinder wall clearance. Just let it warm up a few minutes before putting a load on the engine and it's fine.
Question when you wait for the security light to show up then you wait 10 minutes what do you do if it cycles there the the oil change then battery now then security do I still wait the 10 minutes or what
You have to wait for the security light. This truck had problems with the battery. It shouldn't happen, but if the battery is low the light messes it up. So you have to keep it charging while you do this or else you have to start over if the battery runs out.
Since I bought my Silverado I only get this code when key is out and door is open, no other issues, I also don’t have a fob and I think the key cylinder was replaced Waldo adding a new key, but other words works just fine, should I be concerned about it?
My security lights turns on, when i plugged the big ebcm connector back into the module. And now it cycles battery, low fuel, and security on the message center and wont start and no gear selector square on the gear display and when key is out it’s just solid security light. Then when i unplug it, everything thing works again. Do you think this will fix it?
I have a 2014 Chevy suburban 5.3 it has an aftermarket anti theft you hafe to turn the turn signal on to crank it however the other day my wife drove it to the store parked and it died now it will not crank everyone that’s looked over everything says it’s the anti theft any suggestions or help??
@@MattsShophey i’m going thru the same thing right now. But i think i have a bad fuel pump. does the flashing security light have anything to do with the fuel pump? it will start tho if i press the gas pedal while cranking.
@@MattsShop I just baught a 01 chevy Tahoe and day one it ran fine but the security light was flashing, day two the security would just flash and no start, I was having other issues with the aftermarket remote start that I think I got disabled but my security light was still on and wouldnt crank or nothing until I tried to start it in neutral and it went to it would crank fire but wouldn't stay running until I unplugged and plugged back in the passlock or whatever it is on top of the ignition switch and it fired right up, but now of my doors are locked and I open any other door with the key the horn goes off and after shutting the Tahoe off the security light come on with the door open and stays on after locking and closing the door for a few seconds then the security light shuts off but didn't come on when I left it unlocked, is this normal now! No security light while engine is running noe either! when I baught the Tahoe the guy had the battery disconnected for weeks, do you think thats what caused the whole problem, Or do I still have a gremlin somewhere in the wiring?!
I have another issue on top of this one. I replaced my ignition cylinder (had to drill it out after tow truck fucked up my shifter column and did something to make my key stop turning to the run position) but now with the new ignition cylinder in, the key won't spring back on its own. It has friction inside the cylinder housing. I can firmly turn it from on to run, but have to manualy turn it back to on from run as well, it won't spring back on its own. It just stays where i put it between on and run. It does not have this friction in the off position, it moves freely there. It also won't turn to the Accessories position at all. Iv taken the ignition switch out and tested it with it out and the spring back works on the ignition switch so iv come to the assumption my cylinder housing is fucked up now.
@MattsShop howdy again. I have a question. My 2004 cateye with the 4.8 has just developed a cel and it doesn't have any service warnings. I popped the hood while it was running and I could see the boot of the rear most cylinder on bank 2 shaking more than the rest. The rest were just a little loose, barely a wiggle, and this one feels a lot looser. It did seem like it lost a bit of power and throttle response so I would assume it developed a mild misfire. I don't have a scanner though, so I can't just check. I'm fairly certain its not the knock sensors because it doesn't do the ol "knock test" on startup and I'm unsure if it's an 02 sensor. I know it's nothing major because it still drove and accelerated decently, just not what it should.
Mine flashes security when my key is out of the ignition then turns off after about 20-30 min then if I use my power locks my security system stays solid orange. It’s never happened when my truck is on and running though anybody have an idea of what it is?
dude this helps so much! I did a 4.8 to 5.3 swap on my truck and couldn't figure out why the ECM from the 5.3 truck wasn't working haha.
(donor truck is identical to swap truck in every way except it had a 5.3 instead of a 4.8)
You're welcome! That's one of the main reasons you have to do this procedure.
I had this issue once, reprogrammed the key to the truck no problem. Happened again a few days later. Then again. And finally I took it to the dealership. They wanna replace the passlock sensor for $968!
When you going to do a video about the infamous ls lifter tick 👀
I had a 2003 Tahoe LT auto ride. It had all-wheel drive leather DVD player 5.3 l pretty much every feature and yet it was only a regular Tahoe. A pretty rare truck. You'd even had DVD player. Like I said, it was actually more loaded than my current O2 Denali which I love
what if the security light stays on?
I'm having same problem I have a 99 tahoe
@@codyrichey810me too and my head light don’t turn on
Me too 99 silverado
04 monte carlo 3.4
When I was young my dad had a square body but then he had a GMT 400 and then he ended up trading that in and getting an 800. I spent a lot of years behind that 800 dashboard and now I drive one. Myself and my children sit behind an 800 dashboard
I got 02 Denali pretty sure it's been bypassed and the air ride system definitely been bypassed. Couple other things too for sure. She's an old family hauler still hauling future GMT 800 Lovers
2003 Chevy Express cargo van power wire 0 location?
A company in Florida makes a bypass for the air rides. It goes on the computer in cargo area. Also theres a module under the spare tire. It rots along withe the tire carrier. Causes no starts and service suspensions light s. Cut brown and brown/ white stripe and tie together. Fixes the ride contteol light
What if I have to do it everyday to start it
I've heard you can put four-wheel drive transfer case in an Escalade or Denali and make it four-wheel drive well actually it will be two-wheel drive or all-wheel drive. Not four wheeler. But still that would be cool. It will shave gas, be able to do burnouts and less wear and tear on the components cuz the all-wheel drive heats up suspension and steering components
The security system will never shut the engine down while driving. That would be a safety issue. If the system fails while driving the message will come on but continue to run until its shut off. So if you have a stall concern while driving its not the security system that caused the stall
A lot of guys have had their truck die while driving and the security light comes on.
@@MattsShop That would be a module failed and caused stall and during the failure it lost the passcode for security system. Root cause wasnt the security system. Start a vehicle and while its running unplug the passlock sensor. It will continue to run and the security light will come on.
@@jeffco908Are you a little on the slow side ?
I have vats problems . Wires were loose in the black clip the red yellow and black wires run to on top of the barrel. Di they sell new connectors and wiring for that?
My 99 chevy express..5.7..i replaced the pcm 4 years ago..run great...for a while now my engne will start, die etc.then would start, run good...the other day my battery went dead from headlighrs left on...now the engen starts and dies...im wondering if it needs a 30 min reboot?
Hey matt can you please explain the cold start on this engines that knocks for about 2 minutes and then goes away? I been trying to figured out but it looks like you know a lot about this engines
Piston slap is what I've been told. Pistons need to heat up and expand to take up the piston to cylinder wall clearance. Just let it warm up a few minutes before putting a load on the engine and it's fine.
Will this work on a 02 lb7?
Question when you wait for the security light to show up then you wait 10 minutes what do you do if it cycles there the the oil change then battery now then security do I still wait the 10 minutes or what
You have to wait for the security light. This truck had problems with the battery. It shouldn't happen, but if the battery is low the light messes it up. So you have to keep it charging while you do this or else you have to start over if the battery runs out.
On my 1999 Sierra the security comes on-dash but it doesn’t do anything I just want to find out what causes it to show while driving.
You gotta hook it up to the TECH2 scan tool.
Since I bought my Silverado I only get this code when key is out and door is open, no other issues, I also don’t have a fob and I think the key cylinder was replaced Waldo adding a new key, but other words works just fine, should I be concerned about it?
If it's fine don't worry about it. It's supposed to come on when you lock the truck too.
My security lights turns on, when i plugged the big ebcm connector back into the module. And now it cycles battery, low fuel, and security on the message center and wont start and no gear selector square on the gear display and when key is out it’s just solid security light. Then when i unplug it, everything thing works again. Do you think this will fix it?
If you disconnected that system, can you still use your key fob and your GM key
It's a good question. I know the 1999-2007 Chevy trucks don't have chips in the key so it doesn't matter. Not sure about the key fob.
I have a 2014 Chevy suburban 5.3 it has an aftermarket anti theft you hafe to turn the turn signal on to crank it however the other day my wife drove it to the store parked and it died now it will not crank everyone that’s looked over everything says it’s the anti theft any suggestions or help??
My security light comes on after my battery died,but I can still start it with my key?
It's supposed to flash on and off with the door open or locked. If it does it while driving or won't start you got problems.
@@MattsShophey i’m going thru the same thing right now. But i think i have a bad fuel pump. does the flashing security light have anything to do with the fuel pump? it will start tho if i press the gas pedal while cranking.
@@MattsShop I just baught a 01 chevy Tahoe and day one it ran fine but the security light was flashing, day two the security would just flash and no start, I was having other issues with the aftermarket remote start that I think I got disabled but my security light was still on and wouldnt crank or nothing until I tried to start it in neutral and it went to it would crank fire but wouldn't stay running until I unplugged and plugged back in the passlock or whatever it is on top of the ignition switch and it fired right up, but now of my doors are locked and I open any other door with the key the horn goes off and after shutting the Tahoe off the security light come on with the door open and stays on after locking and closing the door for a few seconds then the security light shuts off but didn't come on when I left it unlocked, is this normal now! No security light while engine is running noe either! when I baught the Tahoe the guy had the battery disconnected for weeks, do you think thats what caused the whole problem, Or do I still have a gremlin somewhere in the wiring?!
2003 Chevy Express cargo van power wire 0 location?
I have another issue on top of this one. I replaced my ignition cylinder (had to drill it out after tow truck fucked up my shifter column and did something to make my key stop turning to the run position) but now with the new ignition cylinder in, the key won't spring back on its own. It has friction inside the cylinder housing. I can firmly turn it from on to run, but have to manualy turn it back to on from run as well, it won't spring back on its own. It just stays where i put it between on and run. It does not have this friction in the off position, it moves freely there. It also won't turn to the Accessories position at all. Iv taken the ignition switch out and tested it with it out and the spring back works on the ignition switch so iv come to the assumption my cylinder housing is fucked up now.
Replace the entire steering column
what did your PCM cost you, want to put an LS in my 46 truck
If you go to Flashmastersecm.com, you can look up your PCM. They had good deals.
@MattsShop howdy again. I have a question. My 2004 cateye with the 4.8 has just developed a cel and it doesn't have any service warnings. I popped the hood while it was running and I could see the boot of the rear most cylinder on bank 2 shaking more than the rest. The rest were just a little loose, barely a wiggle, and this one feels a lot looser. It did seem like it lost a bit of power and throttle response so I would assume it developed a mild misfire. I don't have a scanner though, so I can't just check. I'm fairly certain its not the knock sensors because it doesn't do the ol "knock test" on startup and I'm unsure if it's an 02 sensor. I know it's nothing major because it still drove and accelerated decently, just not what it should.
@@MattsShopalso, I will note that at idle all the spark plugs but that rear most one are completely still.
How do you do it for a 1998 chevy 3500?
Mine never says security so it must be bypass
What if the security light doesn't come on. Its on when truck is off
Same issue
Power wire
2003 Chevy Express cargo van power wire 0 location
Where are you talking about?
Mine flashes security when my key is out of the ignition then turns off after about 20-30 min then if I use my power locks my security system stays solid orange. It’s never happened when my truck is on and running though anybody have an idea of what it is?
Door locks inside the panel has a sensor and needs a replacement
2funny