hello fellow 240 owners
my partner and I got an '87 over the weekend and holy smokes is it a project. the "sound guy" we bought her from made an absolute mess of the wiring. and I'm trying to figure some stuff out and would appreciate any help!
so we have taken out the entire interior in order to restore it which makes accessing things so, so much easier. last night on the way home the tail lights stopped working (turns out that was just a relay) bu then a few minutes later the central lock/unlock got super wonky. was sporadically unlocking and locking all the doors and heard a rapid clicking coming from seemingly the relay. i've done some research on the this and suspect it's because the door switch control is being held up by a flimsy *** piece of duct tape HOWEVER-- the FR door has a different lock from the driver's side door and isn't connected to the central lock system, I thought I'd look around and see if I could get it connected-- figured it out, made the connections between the blue and yellow wires, went to put the fuse back in and it immediately burned me along with specifically the FR door locks going bonkers??? I've also noticed pretty much everything associated with fuse 8 is not working as well? I'm very confused please help!!

 

A 240 with central locking - The drivers door has 2 switches that control the electric locking system. The drivers lock stick has a spring loaded switch in it and there is a switch that is wrapped around the key lock on the drivers door. Twist the key and it makes contact (inside that plastic thing) to lock or unlock the doors or push/pull the stick and the spring loaded switch does the same.

All the other doors and trunk/cargo door only have an electric motor the locks or unlocks them. Power to all the motors is sent from two relays located under the center vents on the dash. An up relay and a down relay.

There is no electric motor in the drivers door to lock and unlock the door - it is only unlocked by the mechanical action of the key turning or the stick being pulled up.

 

Yes, I’m very familiar with the fact there’s no electric motor in the drivers door. Also I’m aware where the relays are located. Are you saying this could be an issue with the relays?

 

What's the issue? Clicking and sporadically locking/unlocking?

Those lock/unlock signals can only come from the drivers door switches - (unless some wiring is missing insulation elsewhere) Just unplug the 3 wire multi connector going to the 2 switches under the drivers door panel and see what happens.

What's the deal with the rf door that "has a different lock from the driver's side door and isn't connected to the central lock system"

The rf door lock (and all the others except the drivers door) has an electric motor that pushes or pulls with a rod the lock lever on the inner door latch assembly - so I don't understand the question.

 

Yes sorry let me be more clear, the issue is the clicking and sporadic locking and unlocking.

Will try that out and see what happens.

There’s a separate key for the fr door and it was the only way the previous owner knew to unlock the door, that’s what i meant by different lock. This is a separate problem I suppose my bad lol but still connected to the original issue. Anyway, I followed the blue and yellow wires from the motor and noticed it was disconnected behind the glove box, so I reconnected the wires, went to put fuse 8 back in and seemingly specifically that door’s lock started going nuts. Before, when that was disconnected, the fuse would be in and it would be fine. Not burning out or anything. But when I made that connection to the fr motor the fuse immediately got really hot and burnt. I guess typing that out, I now realize why that happened.

I’ll try what you said about the multi connector but am I on the right track thinking this could be an issue with the relays?

 

Unplug the 3 connector plug to the drivers master lock switch - Commonly the wires going to the part wrapping around the key tumbler get pulled out or damaged and send the wrong signals.

The passenger door may have been replaced with a complete door - and the existing tumbler was left in - it was cheaper that way. You may still be able to order a replacement tumbler from the VIN number from Volvo if it bothers you enough - (for the rf door) As long as the ignition and left door tumblers (and the trunk) have not been changed Volvo will have a record of the key code and can build a new lock that works.