Need some advise on where to start when power door lock stop working on a 1987 coupe

Need some advise on where to start when power door lock stop working on a 1987 coupe

Whats happening are they not working period? Or under certain times?

Driver side now works but left side manuel lever only slighlty moves when drivers door lock it pushed.

Driver side now works but left side manuel lever only slighlty moves when drivers door lock it pushed.

Sounds like low voltage to the lock solenoid. Almost certainly caused by corroded connectors or an old and degraded switch on these old beaters of ours. I'd start by taking off the door panel and trying to get a voltmeter on the connector closest to the solenoid. If its much below battery voltage then that's most likely the problem. Comparing it to the working side at the same connector would give you the best idea of what it should be since it's, uh... working. It could also be a mechanical bind due to rust or crud but my money is on electrical.

If you find low voltage you'll need to start working (checking voltages) upstream and cleaning connectors until you get the volts you need at the solenoid. If you can read the voltage drop across the switch it should be less than... I'd say about .2v when actuated (switch is pushed) to work reliably.

One thing to keep in mind is that the voltage could be VERY different by just checking it with the connector unplugged. You will most likely still read 13.5v (battery voltage) You need to measure it while connected to see if there is any voltage drop occuring at one or more of the connectors. This will only happen if the circuit is complete (connector is connected).

My first post here

Thanks for the direction, I will give it a shot.

Gary