I just purchased an 89 coupe with 20K and the locks are doing strange things.
The drivers door switch will only unlock the doors and the passengers door will only lock the doors. No unusual noises.
Any ideas?????
Assuming the car is stock and no keyless entry system has been installed the only explanation is both door lock switches have bad contacts inside the switch. You could try spraying some electrical contact cleaner inside each switch and work the switches back and forth and see if that cures the problem.
If not you need to remove both door panels and gain access to the door lock switch electrical connectors.
Both door lock switches need to be connected for the power door locks to work.
Driver side switch
Pin A Orange/Black wire hot all the time 12 volts
Pin B Black wire (could be Light Blue)
Pin C Tan wire
Pin D Gray wire
Pin E Light Blue wire (could be Black)
Passenger side switch
Pin A Orange/Black wire hot all the time 12 Volts
Pin B Black wire and is ground
Pin C Light Blue wire (could be Black)
Pin D Black wire (could be Light Blue_
Pin E Black wire and is ground
On the driver side if you take a piece of wire and jump the Orange/Black wire which is hot all the time to the Tan wire that should cause both doors to lock. If that works the Driver side door lock switch is bad.
On the passenger side if you take a piece of wire and jump the Orange/Black wire to Pin C Light Blue wire the doors should unlock. Some people have said the factory schematic is wrong and the Light Blue wire and Black wire shown going between the two switches is transposed and a Black wire will be connected to Pin C of the switch and Light Blue wire to Pin D. In that case jump the Orange/Black wire to the Black wire at pin C and both doors should unlock.
Picture of the door lock switch connector.
