I recently bought a 1997 buick park ave. ultra from my in laws. They threw the remotes away because they did not know any better that there is a battery in it. My wife went out too buy a new remote @ the dealer 72.00 plus a 30.00 synch fee. Well I have the remote but, I have not went to the dealer too get soaked 30.00. I seen thru a link for used remotes for under 20.00 and synch papers instructions come with it. MY question is does any one out there know what too do too synch. the remote to the sensor for free???
You probably can “google” and find out for sure but you can try one of two ideas I have. Ground pin “G” on the data link connector. The data link connector is where the mechanic plugs in his scanner,pin “G” is on the top row all the way to the right,that is top right pin,set it to ground with a lenght of wire. Second place to look is around the radio antenna base. At times GM will put the program mode wire near the antenna base. It will just be a free wire hanging out of the loom with a plastic connector on it. I have seen on some cars with two wires in this connector,if this is the case bridge the gap between them.Otherwise ground this wire
If either of these methods is correct the power locks will cycle,then press and hold any button on a remote until the locks cycle again (should be almost instanteous) before removing the ground or bridge you have made repeat with second remote.
If you have a test light or multimeter test pin 'G" for voltage (there should be none). I would hate for you to blow a fuse.
Remember the locks cycling is the signal that you are in program mode (you say sync. but this is a different feature,you want to program).
Never did a Buick, wish I could be more exact. At least you are not into the years where this was done through the door lock switch or the radio.
Let me go take a look at the schematic and see if I can post any additional info.
I conclude the batteries in the remotes are healthy.