Sinister-one

Well it happened.... the FOB battery died so I replaced it. Now the FOB won't resync or relearn.

Do I need a new FOB ?

Lee DeRaud

What year car? On the newer fobs, the clip that holds the battery has an incredibly flimsy solder joint to the circuit board: could be it broke loose while changing the battery.

(Same may also be true for the older fobs, but I've never seen one so I have no idea.)

65GGvert

You might also check to make sure you have the battery right side up and seated properly. I'd also measure the voltage (3v) on the battery to be sure you didn't get a dead one.

Sinister-one

Ordered a replacement fob..... oh well, we'll see how this goes.

Sinister-one

Well hell..... got a new fob and the car still won't train it.... WTF is going on !?!?!!!!!!

65GGvert

Did you get the correct fob for a 2000 (assuming that's what you have)? Does one fob train and not the other? Does the DIC come up with "train another fob" after the first one trains?

$$$frumnuttin'

did you hold the lock and unlock buttons down for 10 seconds (or less) simultaneously near the car? That always works for me on my '97. The horn will beep when synced.

Sinister-one

Yes I got the correct fob. The numbers on the new fob match the OEM one I have. The cars system WON'T train the original or the new one....

Yes and nothing works.

$$$frumnuttin'

ok, here's a wild one, but you might try a new CAR battery. I just put a new one in and all sorts of weird gremlins disappeared. I was running an optima that was slightly discharged and I didn't know it....maybe around 10 volts or so, car would start fine, but other things just weren't working right. Once I put the new battery in, it's like a brand new car. Problems I was having were with the A/C controller, CD deck, etc. All were magically fixed with a new battery. I think the PCM reads a lot of voltage inputs, and if they are below a certain threshold you get gremlins.

LoneStarFRC

Are your TPM sensors in the tires the originals?

rrichar2591

Are you getting tire pressure read outs ok on the dic? The receiver that receives the signal from the fob also picks up the signal from the tpms. Just trying to eliminate that as the problem.

Sinister-one

I'm not replacing a perfectly good battry...

Yes they are and they work great.

the TPS are working just fine...

Sinister-one

Okay, one month later and I STILL can't get either FOB to work..... I'm at a loss here....

Any ideas guys ??

duramaxsky

If you have a 2000 it takes the old fobs and receiver. I think they had problems with the receiver. You could get the update kit from GM Parts house. I may have the old receiver from my 98. It worked when I took it out.

Sinister-one

So what's the cost of replacing my anti theft system ???

Groveman

Did you try reprogramming it using the DIC instead of just holding the lock and unlock buttons together?

Matching Transmitter(s) To Your Vehicle
(NOTE: You can perform the matching procedure on your own and do not need to go to a dealer to have this done.)

Each remote keyless entry transmitter is coded to prevent another transmitter from unlocking your vehicle. If a transmitter is lost or stolen, a replacement can be purchased through your dealer. Remember to bring any remaining transmitters with you when you go to your dealer. When the dealer matches the replacement transmitter to your vehicle, any remaining transmitters must also be matched. Once your dealer has coded the new transmitter, the lost transmitter will not unlock your vehicle. Each vehicle can have only three transmitters matched to it. To match transmitters to your vehicle:

1. Turn the ignition key to ON.

2. Clear any warning messages on the Driver Information Center (DIC) by pressing the RESET button.

3. Press the OPTIONS button on the DIC several times until the blank page is displayed, then press and hold the RESET button for two seconds.

4. When the message FOB TRAINING is displayed, push the RESET button once. The message HOLD LK + UNLK 1ST FOB in the DIC will be displayed.

5. Press and hold the LOCK and UNLOCK buttons on the transmitter simultaneously for 15 seconds.

6. When a transmitter is learned (matched), the DIC will display FOB LEARNED and then prompt you to learn the next transmitter.

7. Repeat Steps 5 and 6 for each additional transmitter.

8. Remove the key from the ignition.

The programming mode will shut off if:

You don’t program any transmitters for two minutes.

You take the key out of the ignition.

You have programmed three transmitters.

Sinister-one

I've done all of the above.... and I still get nothing.

I'll sit in the car holding both buttons and eventually the DIC reads "exiting training".

Nothing I try works.

Lee DeRaud

The tire pressure sensor works off the same receiver as the fobs, so if the tire pressures display correctly, it eliminates the receiver and cabling as the problem. There could still be a problem inside the BCM, but I'd expect anything there to also affect the interior power-lock buttons.
(The exterior key-lock and interior manual locks thankfully are just mechanical linkages, otherwise life would get very interesting in some failure modes.)

Lee DeRaud

Will the DIC still display a pressure if the TPMS hasn't gotten a valid reading from the sensor in some time? (I'm under the impression that the normal update rate once the car is moving is once a minute or so.)

Lee DeRaud

Just to make sure we're all on the same page:
1. old fob died, new battery did not fix
2. new fob doesn't work either
3. TPMS works
4. interior power locks work.
That's only two fobs, right? It's impossible that the new one is bad too, also not impossible that it was delivered with a dead battery since it may have been sitting on a shelf for ten years. You tried a fresh battery in the new fob, right?