Wiper motor issues

69Valiant360 said
I'm not sure if some of you seen my post in another thread (wasn't trying to thread jack) but if you haven't, here is the issue.

My wipers worked fine until a few days ago when I was warming up the Valiant. I turned the wipers on as there was some water droplets on the windshield that annoyed me. I decided to check out the "high" setting, something I have never done in the 3 years I have owned the car. They hesitated, then died.

Ok, yesterday I went to my brothers because he has all the wonderful tools lol. We found out that the motor is getting power from the switch. So, obviously it's the wiper motor. Well, after trying different things hoping to get lucky (like cleaning the brushes), my brother decides to make sure it was getting proper ground. Bingo, that seemed to be the problem....sort of. We ran a wire from the battery to the wiper motor and it worked, but very slowly. Actually, it would run very slowly and stop until you pushed the wiper to get it to go again.

So, we both decided that since we don't have the wiring schematic handy we shouldn't continue until we do so we know which wire is ground.

Well, here's the thing though. I still have the "ground" wire we installed hooked up and the wipers worked perfect when I got back home. Went out to check them again 30 minutes later and they didn't work at all. Then about an hour later they worked just fine again.

Any ideas what is going on here? It's obviously a ground issue, but why are they acting all crazy with a permanent ground from the battery?

Edit: Sorry, when it comes to electrical issues I am clueless.

ANYTIME there's an electrical issue with one of our beloved old Mopars the FIRST place to look is at that wiring harness bulkhead connector. The engine compartment side of that bulkhead takes a beating over time: road salt, coolant leaks, oil leaks, rain, road debris.... everything get's splashed back against it and it usually corrodes. This is a big reason that dash lights go dim with your foot on the brake, or with the heater on. Plus from years of vibration they actually bend a bit and get loose, and then there's too much resistance in the circut. What your probably seeing is a good ground now with the jumper wire, but marginal voltage through the power side. That's because of the bulkhead connection. Once it's cooled-off it starts to operate, but then it's generating heat because of the resistance. Then it stops working...and "sometimes" goes *poof*.

I would start by dis-connecting the wiper motor harness and visually checking to see if the metal terminals look green-ish gray. If you don't see metal where there was contact, there's corrosion. You can try and scrape off the corrosion and bend the female connectors tighter ( if that was only true in real life....) There are also some commercially availiable spray cleaners that will do a decent job of cleaning, but make the contacts tighter is key here.

It's a crappy, time consuming job, but if you pop the bulkhead connector out of the firewall you can pull it back from under the dash and get comfortable with a drop light and a SMALL pointed pick and bend the female connectors together tighter. From the engine compartment side just clean the male ends. This might also help with charging system problems, lighting issues, and drivability gremlins. And make especially sure to clean those two big old 12 gauge wires that run inside for your amp gauge. When those puppies get skanky, ALL SORTS of problems arise.

Good luck and let us know how you made out.... :thumrigh: