Door Lock Issues

[Armalite15]

I know there are a number of threads about door lock issues but I can't seem to find one that addresses the issue I'm having. Sorry if I didn't read deep enough. The truck is a 1996 K1500 extended cab 2 door. The problem with the locks just started. I tested the remote and it the battery is good and it is transmitting. The fob would not lock or unlock the doors every time, sometimes it would work sometimes not. I did notice that even when the fob did not unlock the doors the dome light and cargo lamp do come on. However when this happened the master switch would not lock or unlock either. The truck has just over 160,000 miles so I thought maybe the master switch was the problem so I bought a new AC Delco switch and installed it, same problem. I've been searching forums so today I ordered and installed a door lock relay and replaced it. Same thing sometimes the fob or the switch will work two or three times in a row then nothing. So the fuse obviously is good, master switch has been replaced, relay has been replaced, and key fob is transmitting. Thanks in advance for any suggestions.

 

[Armalite15]

Bump for hopefully some replies. Is this something really simple and obvious that I'm overlooking? As stated above replaced master switch, replaced door lock relay, checked key fob. Doors lock or unlock sometimes with fob or with switch. If fob doesn't work neither does switch. However fob turns on dome and cargo lights every time even when it does not unlock doors.

 

[kennythewelder]

How does the door locks work with the switch on the door. Could be the motor in the door.

 

[Armalite15]

Both door lock actuators work, when they work, when they don't neither door locks or unlocks.

 

[Eveready]

Intermittent sounds like a stray ground somewhere. Maybe it is something oxidized and not making good contact. Good luck and post when you find it !

 

[95C1500]

I'm having a very similar issue. My driver door lock switch is intermittent. Passenger works every time. But since GM designed these system where everything runs through the driver door lock, my keyless entry doesn't work when the driver switch decides it doesn't want to work. It's an annoying PITA. I haven't been able to find the problem yet.

 

[Armalite15]

Yeah my issue is neither door will lock or unlock with fob or either door switch when they are not working. I replaced the driver door switch with OE Delco and same issue. But as I said when you attempt to use the fob even when the door do not lock or unlock the dome light and cargo lamp both light up. You can hear a clicking under the dash which I thought was possible bad relay. Replaced it and same issue.

 

[95C1500]

I installed an aftermarket keyless entry system on my truck a couple months ago (my lock problem is unrelated, they didn't work right before hand) and the kit uses 3 relays. No factory relay on mine though. When I hit lock, the park lights flash and the horn honks. When I hit unlock the horn honks, park lights flash, and my interior/cargo lamp come on for 30 seconds. Whether the doors lock/unlock or not, the lights, horn, and relays work as they should.

A clicking relay means it's working. It's what they do. It's a strange issue for sure.

 

[1997]

had simliar issue on a 94, yeah, no remote but, replaced driver side switch, same prob. Short story, replaced pside switch as well, good to go.
grounds and rust issues are rare in BC vehicles, but might be in your part of USA, so verfing them 1st is good advice.
if the pside switch price isn't outrages, might be worth a try?

 

[Armalite15]

Passenger much cheaper than drivers side I've already replaced, I'll give it a shot and see.