How To Fix the MR2 MK1 Driver's Window Switch For Free

(Maybe I Have Enough Tools Now...)

By Dr. Hess

Tools Needed:

various screwdrivers

needle nose pliers (smaller the better)

small punch

drill bit index

engine Lathe

Parts Needed:

Piece of aluminum stock approx 5mm x 25 mm

 

A quite common MK1 problem is The Dreaded Driver's Window Switch. I had been nursing mine along for a year now, but it finally gave out entirely. It had been working if you pushed far enough and jiggled some, but no more. Well, a new one is, what? $180?. No junk yard or parts car has a working one because they all break, so I thought I would take a look at the old one.

Take the combination switch out of the door by putting a flat blade screwdriver under the switch cover at the back (end closes to the driver) and gently prying up. Disconnect the plug, remove the cover (2 phillips screws). I am going to call the part you put your finger on the driver's window switch toggle ("The Toggle"). The Toggle pivots on a pin that runs transversly and can be removed by carefully pushing the pivot pin over to one side, working a screwdriver between the toggle and the ear that holds the pivot pin and gently prying to slightly spring the ear, working the toggle up. Once clear of the ear, push the pivot pin in on the other side, and the toggle will be free.

The toggle has three little "buttons" inside it that are spring loaded. They each ride in their own cylinder cast as part of the toggle and push down on the middle of three little W shaped contacts inside the switch housing that are the actual switch. When the cylinder is pivoted by your finger, the button is pivoted into the W and contact is made as the W pivots down. The W's are in loose, so watch out for them. The center cylinder is the one that breaks, stopping your window function. Close examination of the part reveals the design defect: The cylinders that the button ride in are actually round inside and square on the outside. The lateral aspects of the cylinder have cut-outs cast into them, so the entire force of pushing your window button actually is held in place by two small areas of plastic about 2mm x 1mm x less than 1mm. Guess where it breaks? 

I experimented with super-glue to try to hold the broken cylinder back together without success. If solid plastic was not strong enough on this tiny area, super-glue will probably not be either. Eventually, I decided to replace or actually supplement the plastic cylinder with an aluminum cylinder. Any material would work, but aluminum is pretty easy to work with, so that is what I went with. I cut a chunk off of an aluminum spike (no idea where it came from) and turned it down to round to an outside diameter that would fit inside the remains of the broken middle cylinder. I then bored a hole through it with a drill just big enough so the little button would fit inside (but not loose).

I believe it was .152". This gave me basically an aluminum straw about 10mm long or so. I cut a notch in one end so that it would ride saddle-like over the pivot pin in the toggle, cut the length to be about the same as the other two cylinders and super-glued this to the remains of the middle toggle. After letting the glue dry, I put the springs and buttons back in their cylinders and reassembled the switch. At this point I found that the W contact was not working in the up direction, so I took it all apart again and bent the up leg of the W a little so it would hit, then reassembled it again. Works. 

Total Cost: Free. (not counting electricity, time or the aluminum spike I found in my scrap box).

 

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