Volvo Repair: 1990 740 turbo wagon power door locks, power door locks, fuse panel

Question
1990 740 turbo wagon power door locks

After jumpstarting my car, 3 passenger doors  (these locks were replaced by a reputable Volvo shop 6 months ago)would not unlock or lock with the driver door locking system. The rear hatch still opens with the driver door lock. Fuse is good, I would like to know how to get to the relay to check for faults,
I read on the website that one model has the relay located under the front dash between the vents, any tricks on removing dash?  Thank you in advance for your time. Best regards, Bob

Answer
I would need to see a wiring diagram of the system do not work on many of these anymore.I believe there is a switch at the drivers door lock that sends a signal to the relay to operate the other locks.the relay is behind the ashtray below is how to access the relay.


the relay is located on the fuse panel behind the ashtray.remove the ashtray and then remove trim around lighter socket then you will see 2 screws remove the screws and the storage area will come out.