Hello guys,

Looking for some insight here if someone can assist me.

I recently found out my 94 GMC Jimmy SLT 4x4 had the option of having keyless entry via key fob (was cleaning interior and found the TRW box under the center console).

I purchased a key fob from eBay and followed the programming instructions of grounding out pins A and G. Programmed the fob and woo hoo, I had a working key fob that operated the doors at rear hatch...couldn't be happier right?

Well, here is where it starts to get weird. I went back outside a couple hours after programming and was surprised that the fob no longer operated the doors. Didn't think much of it, so went to ground out pins A and G again and go through the virtually painless process of reprogramming.

Wouldn't you know it, when I would connect A and G, the Jimmy would not cycle the door locks in program mode at all....it just sat stagnant like nothing was supposed to happen. Pulled the OBD port from dash, checked for damaged wires etc, but all looked fine. For the next two hours I fiddled with it, repeating the process that initially worked and no dice...damn thing would cycle into program mode, so I called it a night.

Fast forward to today and for crap and gigs I though to myself, let me try it again...BAM...grounded A and G and cycle mode worked and I again successfully programmed the key fob....so I was once again filled with joy, however...I just went back out there a couple hours after programming and no dice...key fob doesn't work and Jimmy will not go into programming mode.....

Im stumped guys....what would cause the Jimmy to loose its "programming" or "awareness" of the recently synched fob and furthermore....why wont it go into programming mode?

 

Weird problem.

Box loosing programming maybe? What comes to mind is:

Check battery

Check grounds

 

Thanks for reply...

For what its worth...I went out on break today and for s 'n g, I tried the key fob and it worked! Worked like a charm for 5 minutes that I was outside....however at the end of the day, it again failed to operate as it should.

Kind of stumped....really dont wanna pull center console out again, but just might have to.

 

Batteries new, contacts in the key fob clean and making good contact with the batteries at all times?

I had an issue similar with mine. the contacts inside the fob had to be CAREFULLY bent out to make a stronger contact with the battery. After 20+ years, they wear out
Otherwise I would get a new module for under the console

 

Everything looks good with the fob itself. It still works off and on without having to reprogram etc. I think the issue is with that box under the console...when I get some more time I'll dig into it a bit deeper.