Fix: Door Lock Switch

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Fix: Door Lock Switch

Post by Morganizer » Mon Jun 11, 2018 9:40 pm

Last winter, my door locks started jumping up and down. Not very often, just from time to time I'd be driving along and they'd go *CLICK*. Okay, something up with that. Then a couple of weeks ago, I came back to the parked van, and the driver's door was locked, but the two on the other side were not. Okay, the door lock switch isn't working anymore. Here's the repair...

So I removed the door panel, peeled the plastic back, unclipped the pushrods from the actuator, yada yada yada, you can figure that out. Here's the switch on the work bench:
IMG_8453.JPG (592.18 KiB) Viewed 463 times
It's a microswitch, and I had a couple on hand, but they're physically much different from the original, so I decided to take apart and clean the contacts of the switch. You can see I've already pulled off the little plastic flash guard next to the wires.

I drilled out the rivets holding the switch to the actuator bracket. I had to drill the holes in the switch and the bracket slightly larger to fit the bolts that would replace the rivets when reassembling. (darn those Japanese and their metric sizes...)
IMG_8454.JPG (528.78 KiB) Viewed 463 times
Heres the switch, all by itself.
IMG_8455.JPG (576.16 KiB) Viewed 463 times
Sorry, I forgot to take a picture of the switch taken apart, so you could see the insides and the contacts I cleaned. Anyway, I pried the plastic cover off, it popped right open, and there's copper contacts inside. And a little black plastic piece that will get lost in the shag carpet if you're not careful.

Here's the switch mounted back on the actuator bracket, with the little bolts. I think they were salvaged from a piece of computer equipment.
IMG_8456.JPG (625.48 KiB) Viewed 463 times
A close-up of my handiwork. Important to note: I trimmed the bolts with a Dremel, so that none would stick out past the nuts. This is important, as we'll see in a moment.
IMG_8457.JPG (537.89 KiB) Viewed 463 times
And put it all back in the door:
IMG_8458.JPG (453.38 KiB) Viewed 463 times
Then, as I was cleaning up my tools, patting myself on the back for a job well done, I realized I hadn't put the plastic cover over the switch. So I took it out of the door again.
IMG_8459.JPG (420.76 KiB) Viewed 463 times
This is the importance of trimming the bolts: the plastic cover has to fit over them, and the rivets are nearly flush. Presumably the plastic cover helps keep moisture out of the switch, so it takes 30 years before your locks get jumpy, and you need to clean the switch.

So once again, my door locks are doing what they are supposed to do. Just for kicks, I looked online for a replacement door lock switch, to see ho much money I'd saved by fixing the old one, and I couldn't even find any. So I figured I would post here in case anyone else has the same problem.

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Fix: Door Lock Switch

Post by Growlerbearnz » Mon Jun 11, 2018 11:29 pm

Awesome, and well done! Straight into the Technical Reference Library we go.
Nothing says "poor workmanship" more than wrinkles in the duct tape.

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Fix: Door Lock Switch

Post by north54 » Tue Jun 12, 2018 12:25 pm

Good writeup! and I shall give it a try. I honestly thought my door lock relay was faulty but it could very well be the switch.

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