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TR4/4A TR4 Windshield Wiper Motor Issue

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KVH

KVH

Obi Wan
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Somehow I managed to short out my windshield wiper motor and now it won't work.

What I did was accidentally touch one of the green wires to both the casing and its spade connector while the wiper motor was on. Clumsy, I know. I was trying to test it.

There was a spark, and some heat, but not a lot. The motor now seems dead.

Do I dare remove the top cover? What would I look for and what could I do?

[Why can't I just leave well enough alone]
 
Have you checked the fuse?
 
It's out of the car, and dead. I was wondering if there might be internal fault protection, but I don't think that's the case.
 
Well, if it's dead, it can't hurt to look inside and see what happened. But removing the top cover isn't going to tell you much, as it only closes the gear box. The side cover is what exposes the motor.

Just to be sure, though, you are applying power between the two terminals, right? The ground through the housing is used only to 'park' the motor, so if you connect one side of your power only to the housing, the motor will run for only part of a turn (at most) and then stop.
 
Those motors are pretty hardy so I would have to agree that you may not have it wired for operation. I opened mine up to replace that red wire that goes to the parking feature and found that one of the brushes had fallen out when the motor was built -- I knew it was that way from the beginning because the brand new brush was lying in the bottom of the motor housing. Apparently it had run for almost 50 years with the bracket acting as a substitute brush. Had worn a couple of grooves in the commutator but still worked fine. Also works fine with that brush put in place.
 
Thanks for the help and ideas. I guess I shorted it by touching both the positive and the case with the connector I was holding.

Inside the top cover one of the wires to the spade connectors was just blown right in half.

I didn't discover this, Luna Generator/Electric here in Tucson did. I just want to report that this 50 year old shop, with old fashioned shelves and cases full of vintage and newer generators, alternators and small auto electric motors, and with old presses, lathes and bearing machines, fixed it in three hours and refused to charge me anything. The good old days are back again.

I'll take anything they'll work on right back to them anytime. What a great old place. [I tried hard to pay; they wouldn't accept a dime]
 
Those are the kind of places you like to find and frequent.

Scott
 
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