1990 Buick Reatta Factory Keyless Entry Remote Programming Procedure
Before starting the process have both keyfobs at hand. Failure to apply both fobs within the the programming will render the left out remote control not working. If you're only programming one keyfob then program it as remote 1 and again as remote 2.
The entire programming procedure ought to be completed within 30 seconds of grounding VAC reprogramming connector (step 2). In the event the procedure isn't completed then start again at step 1.
1. Turn the ignition to ON.
2. Look in the trunk under the rear shelf between the spot that the speakers are mounted. Ground the green single wire VAC connector located at the keyless entry receiver module (see diagram).
3. Wait for door locks to lock and unlock automatically signifying you've entered programming mode.
4. Push UNLOCK on remote 1 twice (pause one second between presses.)
5. Wait for door locks to lock and unlock automatically.
6. Repeat step 4 and 5 for remote 2.
7. Take away ground wire from green connector.
Troubleshooting: In case the receiver is not located on the back shelf then look for it in the trunk just above the left wheelwell.