I have a 68 Corvette convertible that I'm nearly done restoring and have run into an issue with the windshield wipers. A little background on the car; new dash harness, engine harness, ac and new front lamp harness. Everything went together without any problems and everything except the wipers work as they should.

I've tested the wiper switch as per the Willcox video and it tested ok. I checked for continuity on the limit switch and it also tested ok. When I check for power to the wiper motor with the key off I have power on the red wire coming from the harness side and I know that this is correct. When I turn the key on I still have power to the red wire and I have power to the yellow wire and light blue wire on the three pin connector on the wiper motor. I noticed that checking the light blue wire with a test light that it is very dim and it causes the wiper relay to click. When I turned on the wiper switch with the wiper door open and the button on the limit switch depressed the wiper motor doesn't run. I left the wiper switch in the low speed position and was checking the wiper motor when it started smoking. I checked for power on the connector on the wiper motor side and found that I had power on all three wires and the same on the harness side as well. I removed the wiper motor and bench tested it as per the video on the Willcox website and it no longer functions.

I failed to mention that with the key off I have no power toI the three pin connector on the wiper motor. Also, I checked for power at the limit switch using the test light and it didn't light up with the button depressed. I may have not tested it correctly though.

The fact that it has power on the three pin connector with the key on and wiper switch off doesn't seem correct to me, but I haven't found any information anywhere to confirm if it's right or not.

Is it possible that the wiper relay could be bad or wired incorrectly? It seems odd to me that the three pin connector has power with the key on and wiper switch off and the wiper relay clicking by merely touching the light blue wire with the test light sure seems wrong to me.

I realize that the above is a lot of information to digest and I hope I've written it well enough not to be confusing. I'm hoping that this is something some of you may have seen before and that you can provide some insight into my car's problem. Any help will be greatly appreciated.

 

this might help

 

call willcox.

 

I am curious if you figured out your problem. I am in the same boat. I also replaced all the wire harnesses; however, my 68 is not original. I have a 74 hood without the wiper door, and no vacuum system installed on the car. My original wire harness had been modified to exclude the Wiper Door Limit Switch" and the "Windshield Wiper Override Switch". My new wiper motor also smoked when trying to operate. Knowing that this is a grounded system, I am ordering the Override Switch to install, but I am curious if I can bypass the Wiper Door Switch by connecting those two wires together? I would appreciate any input you learned. Most of my questions do not get answered on the FB group "68 Corvette Owners Group". Kind regards, Bill

 

Yes they are just a breaker style switch so you can bypass the door switch and just hard wire them together. The override switch opens the ground circuit so the wipers would be able to stop on the windshield instead of the parked position. YOu can hardwire that as well so that it is always grounded. What the original issue was that when that was openned and left that way with the wipers not parked, the motor would still have power on the park switch waiting for the motor to stop and open the circuit. That would in turn drain the battery dead over a day or so.

 

Thank you for the input...Much appreciated!

 

good luck