Rear wiper turns on when I start up when it’s hot outside

[Jason Krywicki]

This is a weird one - my rear wiper turns on by itself when I start up when it’s hot outside. Say 80 F and up. It started doing this about a month ago. It’ll stop after a few minutes but will sometimes give me a few swipes when I go over bumps or go harder into a turn. There is also an audible relay like clicking noise when the wiper is turning on by itself and, during this period, I can also hear the click it it decides to pause movement briefly on its own as well.

The stalk switch turns on the rear wiper fine after it’s done its initial uncommanded movement.

It seems like a potentially a bad motor to me? Some research also makes me think it could be a bad wire or corroded connector pin?

Any thoughts?

Thanks!


Sent from my iPhone using Tapatalk

 

[Dale5403]

I doubt it is the motor. First thing I think of is the switch. But it could also be the BCM. You can rtry restting it by doing the following.

You can reset your BCM by turning your vehicle to auxiliary, with lights on, or on automatic, flash your high beams 5 times and pump the brakes 3 times and wait for the battery icon on the dash to blink. This works on my 2021 ST.

You could also try disconnecting the battery for a while.

 

[2020FordRaptor]

This is a weird one - my rear wiper turns on by itself when I start up when it’s hot outside. Say 80 F and up. It started doing this about a month ago. It’ll stop after a few minutes but will sometimes give me a few swipes when I go over bumps or go harder into a turn. There is also an audible relay like clicking noise when the wiper is turning on by itself and, during this period, I can also hear the click it it decides to pause movement briefly on its own as well.

The stalk switch turns on the rear wiper fine after it’s done its initial uncommanded movement.

It seems like a potentially a bad motor to me? Some research also makes me think it could be a bad wire or corroded connector pin?

Any thoughts?

Thanks!


Sent from my iPhone using Tapatalk

It has to be a bad wiring pin. I wouldn’t think it is the motor because it works fine after it had that little fit.