Power Mirror Switch Troubleshooting

Greetings all,

I've been having an issue where my power mirrors start going up permanently whenever the L or R mirror switch is selected.

I took apart the driver's door panel and have the switch sitting in front of me, and I've been going through the service manual page below to try and troubleshoot/fix it. Part of this is to provide some help for someone else having this issue, part is trying to save myself $140 from buying a new switch.



Sometimes when I probe terminals 5 and 9 ("UP" for both L and R mirrors) I have continuity when a side is selected despite not having the UP button pressed, which would explain why my mirrors immediately go up when I select a side.



I took apart the switch above to see if I could fix it. It looks like the 3 white pins in the right-hand switch body are pushed out when the mirror rocker switch is pressed. The white pin pushes against one of the 3 spring-loaded contacts on the green housing, which compresses the spring and bridges the contact on the circuit board.

I cleaned the contacts on the circuit board to see if that improved the function, nothing changed. I believe what's happening is the white pins are getting stuck in the extended position, and the spring force is not enough to push them back into the black housing, so the contact remains closed after the rocker switch is released. I tried removing the pins to clean & grease them, but it hasn't helped.

This is supported by the fact that after I reassemble the switch, the terminals work properly, but when I press the rocker, I start getting 5-9 continuity issues again when a pin gets stuck.

Anyone have ideas for saving this switch? Maybe replacing the spring with a higher tension one? I could try salvaging a spring from a pen/mechanical pencil to see if it works better, or maybe I could file down the pins, but I don't want them to jam inside the housing.

Well, I seem to have fixed it. I was prepared to get a new switch, but as a last effort I filed down the 3 white pins with an X-acto knife until they were slightly smaller circumference, and they slid freely in/out of the black housing without jamming. I still had sticking issues and turned a permanent "UP" into "DOWN" since the lower-left pin started sticking, so I shaved off more and more until I got consistent results.

I also cannibalized two mechanical pens to take their stiffer springs, cut them in half, and replaced the little factory springs on the 3 spring-loaded contacts. They increase the effort of pressing the mirror direction switch, but the combo of this and shaving down the pins seems to have eliminated the issue and I get the correct terminal continuities after pressing a bunch of direction inputs to check for sticking. I also scraped the PCB contacts and used contact cleaner. There are no components to replace in the switch besides the lightbulb, but has anyone even seen it light up before?

Hopefully this helps if you have the same problem.