The 96 / 97 remotes have a built in battery test function. Hold the key fob button in for at least 3 seconds and look for a red flash to come from the IR window.

If the light blinks but still won't open the car, there is a resync procedure that goes something like, hold the remote buton for 4 seconds while aimed at the car then you have 20 seconds to insert the key and turn the ignition to run. ( It might be press the remote button 2 times in 4 seconds then turn the key )