Alreaddy did replace new batteries for key remote but the key remote is not working properly.. What cause is that?? do you know??

I know that this procedure work for Grand Prix and Monte Carlo, tesi it...

KEY FOB PROGRAMMING INSTRUCTIONS
Transmitter Programming
No Tools Required
In the event that a transmitter is lost, program the old and the new transmitters into the memory of the remote control door lock receiver. Up to 4 transmitters may be programmed.


Important
Once the keyless entry receiver enters the programming/diagnostic mode, the programming of the first transmitter erases all previous transmitter programming information. You must then program all of the transmitters.

Program only 1 vehicle remote control door lock receiver at a time. If you program multiple receivers simultaneously, the same transmitter could possibly be programmed to more than 1 remote control door lock receiver.


Perform the following steps:
Sit in the vehicle driver's seat. (actually it’s much ezr from the front pass seat)
Remove the ignition key from the ignition lock cylinder.
Close all of the vehicle's doors.
Remove the MALL PGM fuse from the fuse panel. Refer to Electronic Diagnosis in Body and Chassis.
Turn the ignition lock cylinder to the ACC position.
Turn the ignition lock cylinder OFF, then back to ACC within 1 second.
Open and then close any vehicle door. You will hear a chime when the remote control door lock receiver enters the programming/diagnostic mode. If you do not hear a chime, start again at step 1.

Important
After 7 seconds, you may hear a chime confirming successful synchronization. After approximately 14 seconds, you will hear a chime confirming successful programming.

Press and hold the transmitter LOCK and UNLOCK buttons simultaneously for 14 seconds.
Repeat step 8 in order to program each additional transmitter.

Hope helps.