924S Power window switch wiring

[Andrew Sutton]

I have a 1987 924S, and the power window circuit for the passenger window has been "bypassed" by a previous owner. It is set to only operate with the passenger window switch, and not operated by the driver's side switch. All the wires on the driver's side (except ground) were tied together. Has anyone seen this type of bypass? I'm assuming there is a short somewhere in the harness. Haven't really dug into it yet, just wondered if this was common for a faulty window motor wiring harness.

[944 Ecology]

My best advice is to fix it properly. Get a copy of the wiring diagram (the one for the 84 944 electric windows is easiest to understand) and return the wiring back to original.

Good luck...

[curtisr]

Hope this helps.

[Monkey Wrench]

my guess it it was a repair done because the passenger side switch failed. A PO probably jumped the failed switch so he could open it and maybe wasn't too concerned if he didn't have many passengers. You probably just need to put a new momentary toggle switch in there. The stock one will fit properly, you might be able to find a suitable replacement in an electronics store but you'd have to compare the dimension.

the mysterious part is that even if that switch failed, It still shouldn't have failed to operate from the drivers side if there is a separate switch for that.

in another post someone found that the switch was stuck and causing a dead battery as the motor was drawing power and at it's limit so he probably didn't have much of an indication that this is where the problem was.

I had one in a Volvo that was slow and upon disassembly of the motor found the magnets had come unstuck from the motor case. water and rust were in there.. the motor ran but the magnets were stuck to the armature causing it to run really slowly. the armature was polished by the rubbing. I just epoxied the magnets back in place, cleaned , re lubed and it's worked fine since.


something to look for if you find one is mysteriously slow. I had the same happen to windshield whapper motors.

The state of being not able to open the windows properly is a safety concern

Ive had a few of those switches fail in 4 door volvos and the quick and dirty fix is to steal one of the back switches. there is a switch the same size to disable the back windows but that one is not momentary. there is a fair amount of unnecessary wiring for that "feature" I prefer manual winders , less to go wrong.

if you still have the switch you can look, maybe you can repair it. maybe a broken spring or bad contacts or the switch body came apart a bit. Check continuity with a meter.

[Monkey Wrench]

the wiring diagram shows it is not just a single pole momentary switch, there is more going on here than only that. probably best to have the correct OEM switch.

I think that switch is getting fed power from the drivers side and if the switch is operated by the passenger, it disables the driver's ability to override it. assuming the switch broke, the former owner probably needed to get power through that failed switch so that the drivers side switch could operate the window, thus he needed to jump around those contacts in the failed switch.

its bit confusing because they appear to be switching both the hot and ground to the motor and not ony the hot wire..

I think when that switch failed it also prevented power from getting through from the drivers side switch through the failed switch to the passenger side motor. the jumper was a way to wire around that broken passenger side switch to prevent it from blocking the current path. likely it was intended as a temporary repair while sourcing the new switch.

I suppose you might be able to move the switch and allow it only to be controlled by the passenger side.
If you are tall enough to easily reach the passenger switch maybe that isn't a huge deal? Better to fix it back to original but if the switch fits you might swap the two and disable the drivers side ability to control it. that might save buying the switch if you can simply move the working switch to the passenger side location. I think if you give up that drivers side "feature" then you would only need a single acting momentary switch but to keep it original it's probably somewhat special, having contacts that are open one way and closed when its the other way and a spring in the switch making it momentary.

the two switches appear the same on the diagram so I think you might be able to basically reverse what they had done and make it so it operates only from the passenger door. you might need a jumper over near that drivers side switch to do that.

you probably only need to think that way if the plan is to forget the use of that drivers side switch in order to ( steal it) and not have to source the new switch.

I'd try to source an OEM switch , see if you are up against an issue with the part or if it's cheap or easy to get from another car. If the part is expensive or hard to obtain or you can't afford it then maybe it's reason to scrimp, otherwise just go OEM and keep everything original.

[Monkey Wrench]

after re reading the original post I see the car already works from the passenger side switch and I read that backwards somehow..

The OP wants to put ti back to original , he's not satisfied with the switch only being operational from the passenger side but would like to restore the originality.

I think it's likely there is nothing wrong with the harness. I'd verify if the switches themselves work right first. My suspicion is that it is the switch that failed.. the wiring will route through the door though so it could be damaged at the bend point.

I noticed my car doors open really wide. they do seem to stop before crashing into the fenders, but I wondered if it might have something wrong with the door stop that was allowing them to open so far. maybe its normal but I thought about how wide the door is if you get out with traffic passing in proximity.