Hey Folks. I need some help fixing my power door locks and keyless entry. My driver side door unlocks but does not lock. I tested the switch and found that the switch is working but no power is getting to the motor to lock it. I read that there is a relay behind the emergency brake or in that area. I can't seem to locate that but even if I do I wanted to know a part number so that I could but a new relay to see if that is the problem (or if there is a way to test the relay).
Maybe related or separate - the power lock problem has been with me for years but the keyless remote/fob used to work to at least unlock the driver door and also pop the trunk. That has now stopped working. I read that there is a module in the trunk and wanted to know the part number for that so that I can maybe also replace that in case that went bad or if there is a way to test it.
Pretty sure if your remote will lock the door but not unlock it there is nothing wrong with the relay. If the relay were bad it wouldn't do anything at all. Do all the other doors lock/unlock properly? You may just have a bad lock solenoid on the driver door, works one direction but not the other.
Check wires at/near lock module behind driver's side kick panel (where hood release is) as those wires are subject to damage/wear also...
Especially the Ground Wires there as these are known to cause issues overtime since it is just a Sheet Metal Screw securing it to the Body. Last time I was in the area with the kick panel removed, pulled the connections and cleaned the area to bare metal along with the Wire "rings" and remounted it all using dielectric grease on the connections.
Here is the schematic for the Lock Circuit. Maybe you can use this to verify that all the wiring is ok and you can also see how to bypass the relay to test it. At least using the Schematic you can follow each wire and be sure that at least the wiring is okay and go from there.
'95Caprice SS conversion - Bonny Buckets - 96 Column, Shifter and Console - 3.73 Gear and Herter tune - Z/28 Cluster - Blazer OH Console - Green/Pink bushings - Chromed Impala Wheels - Eibach Springs and Bilstein Shocks - Corvette Engine Dress - the list goes on and still more to do...it never ends.
I believe the circuit for the drivers door lock also runs back through the remote door lock receiver unit in the trunk. A relay there is used to specifically handle the drivers door when you push the unlock button the first time. Others have noted that the relay in that receiver unit fails (contacts arc) over time and replacing that relay puts them back in business. Given your mention of the remote failure, I'd check there as well. Good luck.
Thank you for all the help. I changed the relay this morning and it fixed the problem. The remote failure I had seems to be a key fob problem because when i pulled out the spare fob and put new batteries it worked.