What Caused Rear Wiper Failure?

Dear Car Talk

Dear Car Talk | Mar 26, 2015

Dear Car Talk:

I have a 2001 Honda Odyssey minivan. Its rear wiper suddenly stopped working. I took it to a neighborhood mechanic. He thought that the motor had burned out, so he replaced it. It still didn't work. He tried to replace a coil, located on the driver's side near the back door. That didn't fix it, either. Finally, he replaced the switch. Still nothing. If I try to turn on the wiper, only wiper fluid comes out. Could you please tell me what to do next?

-- Vinod

Go to another shop, where they know how these things work.

Well, let's give him the benefit of the doubt and assume he tested for current, and found that there was current getting to the motor. That's why he figured the motor was bad. I'm not sure why he then replaced the switch or a coil.

But let's leave that aside for the moment.

If current is getting to the motor, the motor is brand new and it's still not working, then the cause of your rear wiper failure probably is a broken wire in the tailgate.

There's a bundle of wires that goes from the body of the car into the liftgate itself. It goes in up at the top, where the liftgate hinges are. Those wires run the wiper, the washer, the rear defroster, the license plate illumination, etc.

After the tailgate is opened and closed 50,000 times, and those wires are bent and straightened out 50,000 times, it's not unusual for a wire to break. And since we're assuming he had current at the motor, I would guess it's a ground wire that broke.

So what he needs to do is test that theory by grounding the motor to some part of the body -- the car's body, not his, Vinod.

If the motor then works, he needs to re-establish a good ground for the motor. And it has to run back through that bundle of wires, unless you want it draped over the seats.

So he'll then cut open the bundle, find the fraying or broken wire, splice it back together, close up that bundle, apologize for selling you $300 worth of parts you didn't need, and send you on your way. Good luck, Vinod.


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