R34 Mirror not moving

[Joshh05]

Hello everyone,

Alright, I'm having a weird issue with my passenger mirror. Both mirrors will fold in, but only the driver side will move when I go to change the position. The passenger doesn't move or make any sounds. 

This issue popped up after the car came back from paint. Have a full respray. First issue I noticed was the passenger window wouldn't move since the painter broke the switch. So I replaced all switches on the driver and passenger doors and reset the connectors to the mirrors.  Sill nothing for the mirror moving. I then bought another set of mirrors to see if it was a motor issue but the new mirror doesn't move either. I reseeded the large connector from the door to the body as well as checked all fuses. I tried to use a multi meter on the connector from the mirror to the door but couldn't get any readings on any of the pins. I also don't know which two I should have been testing. 

I don't know what else to check or where to look. Does anybody have any ideas or suggestions? 

[GTSBoy]

Well, you've done more than most OPs in these sorts of posts have done, so kudos for that.

I would suggest probing the driver's side mirror's wiring while it is being driven in and out to work our what gets voltage when, then do the same over on the passenger's side to see if the power is getting as far as the mirror or not. Depending on what you find, you can blame either the mirror or the wiring. Then you just work either forwards or backwards from there until you find the fault.

FWIW, this stuff is not always easy. The control boxes for the windows and mirrors are opaque black boxes (literally and figuratively) that are hard to understand what's going on inside. But with a known working example on the RHS, you might stand a chance.

The other thing to keep in mind is that it was caused by the person who disassembled and reassembled the door for paint and you should have gone right back to them immediately to get it seen to.

[joshuaho96]

If it helps here's a wiring diagram, it is from an R33 but I'm pretty sure this would be conserved across those two generations, no real reason to change things dramatically:

There is some kind of PCB track system that prevents the motor from being powered in one direction once fully extended/folded but it can be powered the other way around. The top two motors are for actual mirror adjustment, the bottom 4/5 pin are for storage. You apply 12V to 4 and 0V to 5 to get the mirror to go one direction, then 12V to 5 and 0V to pin 4 to go the other way. I would try doing this with a bench power supply, preferably with overcurrent protection and all that fun stuff to reduce the risk of blowing something up. If it folds and opens up properly see if the harness is signaling voltage properly. If it sees voltage and the mirror seems to be fine then I dunno life gets complicated at that point, you have some issue pulling voltage too low to operate in one direction while it works fine in another. Maybe the mirror motor has a bad bushing causing the windings to contact the case in one direction but not the other? Something strange like that.

[Joshh05]

Thank you all for the info and help. I have basic knowledge of electrical circuits and wiring so I am a little out of my element in this.  I had someone test the connection between the switch and the mirror and they said their was continuity through our the path. I don't have a power probe to send power to the mirror directly to see if it will move. It's weird that he said that the path was good. Which would make me believe it was a motor mirror, but I have a different set of mirrors that give the same results. Would it be possible for a power loss to happen at the switch where the drive side works but the passenger isn't getting enough power from the battery??

I will be taking it to a shop that specializes in car electronics in the future to see if they can ID it. 

 

Edited June 26, 2021 by Joshh05