I bought a used C5 with two fobs one of which worked. After a few days the second fob stopped working. I bought two new batteries which did not help.

Is it necessary to reprogram the fob's after the batteries go low or dead? Is there any way to confirm that the fobs still work, and is there a link somewhere to show how to reprogram them. Thanks.

Dave S.

 

Have you got an Owners Manual? If not, download one free at GM Parts House.

 

I'm going through a similar problem myself. Here's what I've learned so far.

1. you need to re-sync the fob after you replace the battery. You do this by standing next to the car and holding both the lock + unlock buttons until the car honks (15 seconds). you can also re-train the fob by pressing the "options" button on the DIC until you get to a blank screen, then hold "reset" until "fob training" appears. Then press "reset." Instructions will then appear on the screen.

2. If you take your fob to a parts house or GM dealer they can test your fob to see if it's sending a signal.

I've done both of those things. The GM dealership said my fob worked. When I re-sync it, it works for about 10 seconds.... then nothing.

I'll be curious to know if you make any headway.

 

webelo, if you have an early C5, that's a common problem. There's a simple repair for it posted on this Forum.

 

I have a 2000.

Thanks for the link...

Just kidding (sorta). I stumbled across the fix I think you're talking about just a little while ago (something about re-soldering connections).

http://forums.corvetteforum.com/c5-t...post1570747451

 

That's right, now go to work!

 

Give this a try, worked for me




TRANSMITTER SYNCHRONIZATION
Resynchronization may be necessary due to the security method used by the remote keyless entry system..
The transmitter does not send the same signal twice to the remote control door lock receiver (RCDLR)
The RCDLR will not respond to a signal that has been sent previously.
This prevents anyone from recording and playing back the signal from the transmitter.
Resynchronization may be necessary under the following conditions:
 The battery in the transmitter is very weak.
 The battery in the transmitter was replaced.
 The battery in the vehicle has been in a low or no charge condition for an extended period of time.

In order to resynchronize the transmitter with the RCDLR, perform the following steps:
 Stand within 1.5 meters (5 ft) from the vehicle.
 Simultaneously press and hold the LOCK and UNLOCK buttons on the transmitter for 7 seconds. (The horn should chirp in order to confirm synchronization)

TRANSMITTER REPROGRAMMING

If the transmitter and/or receiver are replaced, perform the following programming procedure:
 Turn the ignition to ON.
 Turn the radio to OFF.
 Press the RESET button on the driver information center (DIC) in order to clear any IPC warning messages.
 Press and release the OPTIONS button on the DIC to scroll through the display options until the IPC display is blank.
 Press and hold the RESET button for 3 seconds.
 Press the OPTIONS button until FOB TRAINING message is displayed.

Important: If the FOB TRAINING message cannot be displayed, check if the BCM is configured with the correct RPO codes.

 Press the RESET button in order to begin the programming sequence. The message HOLD LK + UNLK 1ST FOB will be displayed.
 Simultaneously press and hold the LOCK and UNLOCK buttons on the first transmitter for 15 seconds. The IPC will indicate when that transmitter is programmed and when to proceed to the next. Repeat this procedure for each additional transmitter or press the OPTIONS button to exit.
 Up to three transmitters may be programmed.

Note: The receiver will cancel the programming sequence if either three transmitters have been programmed or no transmitters have been programmed for 2 minutes.

 

Some of the older fobs will fail with no apparent reason. Some have found that the small black 4-lead device, a contact will break connection with the circuit board. A very gentle resoldering will fix those. Others, just fail and all you can do is to replace them. Gene Culley at www.gmpartshouse.com has the best prices around for them and he's a forum sponsor.