Ariel12Black
Having problems with my door locks on 1995 Caddy DeVille. Doors cannot lock or open from any inside switch. However, can open front left door with remote control, but no other doors open. Remote control does lock all doors. When I push remote open door button front headlights go on. I've replaced battery in my remote control.

Well the remote issue might be that fact that the first push unlocks only the drivers door. A second push right after that will unlock all the doors.

As far as the switches inside the rear doors can not unlock. Only lock. Pushing unlock on either front door however sould unlock all four doors.

Does that help or did you already know all that?

If the system doesnt work like codewise said, it sounds like the relays are bad. I think the keyless system runs a separate relay for lock and unlock. When you hit lock and unlock, listen for a relay click in the vehicle and in the trunk. (That is right around the time when the trunk relay board was started in the deville).

Keep us posted on the results of codewise's advice.