Electrical Short

[Ted F.]

I am working on an early 68 and ran into a mystifying problem. My wipers don't work and it appears to be linked to an electrical issue with the wiper circuit. If I plug the power line into the wiper motor's connection plug, the vacuum door opens like its getting the signal that the wipers have been activated. The wipers don't work however, and further to that, unless I disconnect that power hookup, the battery will drain completely. All wiring is new. I have tried a 2nd new wiper motor (no change), I've added an additional ground wire (no change) and I even removed the washer pump to see if that was the problem (again, no change). I've ordered a new dash switch, but am not confident that that will resolve the problem since the one in the dash now is new. Any ideas out there? As an added data point to this mystery, the ignition key buzzer on my horn relay just stopped working. I replaced that as well, but to no avail. There's an electrical issue somewhere, but I'm at a loss to find it. Any ideas are appreciated. Thanks.

[David M.]

Re: Electrical Short

I recommend stop replacing parts and start doing some troubleshooting:

First you have to study the electrical and vacuum systems. They play together. Get a good understanding of the operational theory with the lockout and override. The owners manual will help. So will the AIM and Service manuals.

1. Do you have the wiring schematic? If no get it. Same for the vacuum sys diagram. Search online for both. Or someone here may help. The
reproduction suppliers have this literature readily available.

2. Do you have power down at the connector on the motor when the switch is on? If yes bench test both motors. You could have two bad ones.
If no power start tracing the system back through the switches eventually to the power source...the fuse box.

[Mark E.]

Re: Electrical Short

Willcoxcorvette.com has nice color schematics for the wiper vacuum and electrical systems.

[Ted F.]

[Rich G.]

Re: Electrical Short

Do you have the wiper over ride engaged? Sounds like what happens when it is.

Rich

[Ted F.]

Re: Electrical Short

Do you have the wiper over ride engaged? Sounds like what happens when it is.

Rich

[Rich G.]

[Ted F.]

Re: Electrical Short