1999 Tahoe door lock/Keyless issue

[Cue777]

I have a 99 Tahoe 4 door and am having a hard time trying to get the door locks working properly. I know I have one bad door actuator on the passenger side, and I have tried diagnosing it with that plugged in and with it unplugged, the rear door one is also bad but I have not unplugged it. The drivers door and 2 rear doors work strong with the door button.

The door locks work fine if I use the button on the drivers door only, they all lock and unlock. When I use the factory keyless remote to lock the door, it locks and then unlocks real quickly like a replay isnt holding long enough. If I hit the unlock button on the remote it will unlock the driver door if it was locked but if it was unlocked and I hold the button, it will lock the driver door but not the rest, and then the lock button unlocks it so they work in reverse, but it doesnt work everytime like that, kind of confusing.

It had a aftermarket alarm hooked up to the locks that I have removed, and I have tried putting power to the wires for unlock and lock that go into the lock relay where the alarm was hooked up to and to get them to work properly I have to put the power to them for a few seconds and hold it on there, just a quick touch and the drivers door locks then unlocks right away like it does with the remote.

I have a brand new remote from GM, I have replaced the door lock relay and the Keyless receiver module and I just dont know what to try next?

 

[Cue777]

Any ideas where to look next?

 

[Squirrelsmith]

That sounds terrible good luck!

 

[Cue777]

Anyone???

 

[RED TAHOE LS]

As for the remote, push the unlock button ONCE unlocks the driver door only, push it AGAIN it unlocks all other doors that are in working order. My original fobs just quit working. I bought one from GM dealer (not much better) finally ordered one from the link below, it works BETTER than even the OEM ones when new. Good luck.
David g...….




https://www.carandtruckremotes.com/... and trucks remotes&utm_content=Branded Terms

 

[Cue777]

It wont do that, I am familiar with how to open the other doors with the second button hit, it wont open on the first press of the lock button, it locks then unlocks itself again. Only hitting the unlock button the drivers door will LOCK, makes no sense.

 

[drakon543]

did it work at all after you removed the aftermarket kit? also do you know if the aftermarket kit had remote start? some gm vehicles in the 90s had a chipped ign key. some aftermarket kits require a chip key bypass to be installed. if it has that and you went back to the factory system it wont let you lock the doors with the remote. the vehicle will think the key is in the ignition and its trying to stop you locking your keys in the car. also the door buttons bypass that system so that could be why the door buttons work and the remote doesn't.

 

[Cue777]

did it work at all after you removed the aftermarket kit? also do you know if the aftermarket kit had remote start? some gm vehicles in the 90s had a chipped ign key. some aftermarket kits require a chip key bypass to be installed. if it has that and you went back to the factory system it wont let you lock the doors with the remote. the vehicle will think the key is in the ignition and its trying to stop you locking your keys in the car. also the door buttons bypass that system so that could be why the door buttons work and the remote doesn't.

The aftermarket alarm was doing the same thing when I hit the lock and unlock buttons on it. You may be on to something though, Ill have to see if it has one of those installed, although I would think that it would unlock the doors after they have been locked with all the doors closed even if it thought the key was in the ignition.

 

[drakon543]

the only other thing i could imagine would not be fun to trouble shoot. same problem with the aftermarket system as the factory system would lead me to think you have some wiring issues somewhere. could be some frayed/grounded wires somewhere in the system. since the vehicle had a factory system already in it maybe the factory receiver was shot. if the factory receiver was bad and an aftermarket got piggy backed overtop of it the trigger signals would still feed back to the receiver. my other suggestion would be to gain access to each lock actuator and check continuity to ground at each one. if you have 3 that are reading the same and one is off at the plug follow it back. ive never run into a situation like yours so im just trying to give you some ideas.

 

[Cue777]

The receiver is new though as I replaced it with no change in its operation.