The auto door locks on my 1991 buick regal quit or only work intermittenly. I bought a new transmitter (hand unit) and replaced the relay under the dash. The dealer could only program the new hand piece to work only the doors not the trunk. Ont the inside of the car the lock and unlock buttons only work once in a while. Are there anymore relays associated with the auto door locks? Tired of opening the dorrs with a key! Wolfman

I had they same problem a few years back. Aging electronic circuits may be the issue here. That is what happened to cause the remote door feature to operate intermittently in my 1991 Buick Regal. Over time the heat of summer and the cold in winter stress solder joints on printed circuit boards. That stress can bring about what is known as cold solder joints.

I located the remote door receiver module behind the back seat under the cover that holds the Third Brake Light. Once removed from the car I opened the module up and inspected the printed circuit. Sure enough I saw the problem using a magnifying glass. Many of the solder points had cracks around connectors, resistors, capacitors to name a few. Resoldering each bad point sovled the intermittent operation. I hope this helps...