Windshield Wipers not shutting off

[Alpine 1789]

As a fair weather Alpine driver, it seems I only use my wipers at events or in preparation for them. As I recall, the last time I used them was driving to the 2018 United. I hit a brief shower and turned them on for about 15 minutes. The wiper motor wouldn't stop when the rain stopped. I pulled off and tried some simple roadside fixes and think I finally just disconnected the wires. All was fine when I later reconnected them.

With SUNI on the very immediate horizon, I just had the car's safety inspection, despite today's rain. The rain was very light on the way there and I only used them a couple of times without incident. It was raining pretty hard on the way home, so they ran for about 10 minutes before I tried to shut them off. Again, they kept going. Interestingly, this time they eventually stopped on their own after a couple of minutes. I started them back up and they ran on for a bit and then stopped again. I don't think this is something I am going to get to before we leave for Independence on Saturday (towing the car this time) but I thought I'd post this now while it was fresh in my mind and try to get some ideas on where to look when I start trouble-shooting. Any thoughts?

 

[mikephillips]

Only a couple things I can think of. First, try swapping the dash switch to see if perhaps it is faulty and the internal contacts not separating right away. Next would be the parking switch in the cap on the top of the motor where the cable to the wiper arms comes out. There's a little sweep in there to keep power to the motor until it hits the parking position when the switch is flipped off. Has a plate on the gear that the motor turns with a dead spot where it should stop, causing the motor to continue to run until the contact in the cap hits that spot. May be that this has failed or something has gotten in that is interfering with how it is supposed to work. You'll probably nee to remove the motor to look at this since the V has the cap flat on the top rather than on the side of the drive like the earlier series.

 

[Tom H]

Jim,

Mike is on target here. Maybe try just tapping the switch to be sure it's not sticking. I doubt that's a likely issue, but worth a quick check.

Most likely it's an issue with the parking contact on the wiper motor assembly.

Scroll down to page 11 here:
15-Electrical-System-N-2.pdf (sunbeamalpine.org)

If you can remove the cubby box, you may be able to access that part of the wiper without removing the wiper. As a temporary fix, I THINK you can disconnect or cut the wire going to the terminal located at the top of the cover. This would disable the parking mode, which would require just a bit of extra care when turning the wipers off to stop them in the parked position.

A better temporary solution might be to add a switch to the Green (power) lead going to the wiper motor. Just let it dangle under the dash, provides an "override" whenever the wipers won't stop.

A way to verify it's parking contact, next time it happens just disconnect only the NLG and RLG connections, but leave thee Green connection in place. If it still runs it's the parking contact for sure.

 

[Alpine 1789]

Thanks, guys. I think I replaced the switch after the first time but I could be wrong on that, so I'll double check that first. But, I had a feeling it was the parking function, too. I like the diagnostics and the patches. It may be a while, unless we get a lot rain in Independence, but I'll report back when I do find the cause.