Relay,
check the numbers on them, if the same number,
"switch it",
because it will work in another circuit, and you can find out if the relay is your problem. GL

 

No need to wave in the future...

1 part of GM's "theft deterrent system", just remove the master switch from the vehicle, take a walk with switch in hand, then take it back to the rig and reinstall the switch.

 

Hummerz shared ..."1 part of GM's "theft deterrent system". I think that's getting closer to my answer.

I had the driver window, power door lock issue, tried all the battery disconnect, checked fuses, etc. Finally broke down, bought a master switch unit from EBay. Disconnected positive and negative, left them touching for 2 hours, then installed new switch, reconnected battery, started car. With car running, driver window worked, doors locked and unlocked.

Turned of engine, went outside car, used remote (just tested works fine). The lights responded but NO locking or unlocking function, AND a quick beeping occurred, continuing until I pressed panic button which set off horn. Pressed it again to turn off horn blasts.

Tried this procedure several times, same thing every time. Anyone have ideas? Sounds like maybe some issue within the theft deterrent?

Thanks!

 

Try your original master switch or the new 1,

1-hit-> key fob unlock, open door
2-unplug both master switch connectors, remove master switch
3-close door, hit-> key fob lock
4-take master switch away from the vehicle(far enough where your key fob won't work)
5-go back to vehicle
6-hit->key fob unlock, open door
7-plug in both master switch connectors
8-start vehicle
9-now check switches & fob


GL

 

I had the same issue with my window and locks after disconnecting the battery for for maintenance. I tried every trick posted and nothing was working. was about to buy a new switch when I decided to try and removed the master switch on last time. This time I just happen to be waiting for the wife to finish shopping and had the truck running. Pulled out my tools and removed the master switch. Waited about 5 minutes and connected it again expecting the worst. Well it worked. Windows all work , locks works , and keyless entry works as well. All is back to normal.

I would try this before buying another switch to see if it works for you.

 

Mine still works after it failed me a year and half ago, when I replaced the battery. The key, it worked before you disconnected the battery, so the switch is NOT defective. The master switch just needs a relearn.

 

Exactly this!! Tried EVERYTHING and nothing worked but this. Master switch re-learn. Thanks so much!

 

"4-take master switch away from the vehicle(far enough where your key fob won't work)
5-go back to vehicle "


the door switch doesn't receive the remote signal. the body control module controls lock unlock from the key fob.
anyway what can moving the switch do? I agree that it needs a reset because of the logic in it and maybe a capacitor needing discharged. I really don't know just where the fob receive antenna is but im looking! I guess it goes to the digital radio and then to the bcm. from the bcm go the lock/unlock signals,but not a key fob signal.


it looks like fuse 8, 20 amp should reset it if pulled for awhile.


its not the onstar antenna , I unhooked mine years ago. from the gps ant ? the fob signal gets to the digital radio and goes out on the data bus to the bcm, from there on lock/unlock wires to the door module.


.
I cannot get the quote tags to work. malfunction somewhere.

 

This thread is 5 years old, you made #128 post, trying to analyze it? Don't lose any sleep over it! I was there, I replaced my battery that was less than a year old (I didn't know that until I removed the cover. I bought the rig used, and already had the new battery in hand), with an optima battery. I ended up with this issue, tried everything posted, NOTHING WORKED! I even tried disconnecting the connectors to the switch and left them disconnected overnight, DIDN"T WORK either. After spending many hours, trying different procedures, still determined that the switch was not defective, I came up with the above steps that finally worked. Yes, as I previously posted, there could be fewer steps, but I haven't tried it again. It could work, performing all of the steps I listed above, eliminating #4, but I haven't tried it that way? I got step #4 idea, from someone that posted, going to a dealer and the tech connected a new switch, which worked.
It appears you have plenty of time on your hands, why don't you try disconnecting your battery terminals, long enough to get the master switch failure, then run the relearn steps that I have listed without #4. That will put your mind at ease. Let us know if it works that way. TIA

 

yeah,relax, I posted a couple times on this thread because someone kept it alive and others and you pitched in. im always looking for final answers or better ones. this doesn't seem to be finished.
not a big deal, keeping the forum alive with input huh.


when someone says move the sw far away enuf.... it makes no sense. no use misleading someone. if you unplug it that's far enuf.
it is a mystery but I don't think it relearns anything. it may get reset.


as far as unhooking my battery , ive done that dozens of times for various reasons with no problems. that does not seem to cause this problem routinely.