I looked into it a little bit. It looks like it has to be programmed by the dealer. ???
2004 Chevrolet Colorado keyless entry remote
This remote has to be programmed by your local dealer or a locksmith.
This worked on my 2003 TB, got #2 FOB off ebay. There so cheap on ebay.
Not sure about Collie, Steve. but here is repost intructions...
Transmitter Programming
Important
All transmitters which are to be recognized by the Liftgate Module (LGM) must be programmed in a single programming sequence. If the system is placed in program mode it will erase all previously programmed transmitters upon the receipt of the programming signal from the first transmitter. Up to 4 transmitters can be programmed. Do not operate or program the transmitters in the vicinity of other vehicles that are in the keyless entry program mode. This prevents the programming of the transmitters to the incorrect vehicle.
You may program up to 4 transmitters, using either of the 2 following procedures:
Method 1 - No Tools Required
Close all the vehicle doors.
Insert the ignition key into the ignition lock cylinder.
Press and hold the door unlock switch.
While holding the door lock switch in the unlock position, cycle the ignition ON, OFF, ON, OFF.
Release the door unlock switch. The doors will lock and unlock to confirm the program mode.
Press and hold the LOCK button and the UNLOCK button simultaneously on one transmitter. After a delay of approximately 15 seconds, the doors will lock and unlock to confirm the programming of that transmitter.
Repeat the previous step to program up to four transmitters.
Turn the ignition switch to the RUN position in order to exit the keyless entry transmitter mode.
Operate the transmitter functions in order to verify correct system operation.
Method 2 - Scan Tool Required
Install a scan tool.
Turn the ignition ON, with the engine OFF.
Use the scan tool in order to access the Lift Gate Module (LGM) Special Function: Program Key Fobs menu.
Follow the directions on the scan tool in order to program the transmitters.
Operate the transmitter functions in order to verify correct system operation.
