Rear wiper randomly wipes when starting the car

[p38fln]

Every couple of days, the rear wiper will make one wipe across the rear window when I start the car.  Is this normal?  It's not reproducable, very random behavior.

[Ephethean3]

The back wiper in my 2015 will also do that sometimes but not every time I tap the front wiper once to clear the morning dew. Any additional taps will not cause the back one to wipe. I don't know why there is no consistency to it but there isn't. I've stopped trying to figure it out.

[ptjones]

I see the same and I have auto sensing wiper position on. :)

 

Paul

[dyee]

Could it be the courtesy rear wipe? If your front wiper is on and you shift to reverse the rear wipe swipes once.

[ptjones]

This could be, It only goes when the front wiper goes first thing when you start up. Usually when it's wet. :headscratch:

 

Paul

[raadsel]

I see the same and I have auto sensing wiper position on. :)

 

Paul

 

I've seen the rear wiper go when switching into reverse. My guess is that it is tied to the front sensor, that if it senses wetness and you've run (or had on auto) the front wiper, it automatically does the rear wiper when put in reverse.

[plus 3 golfer]

From the manual: "When you shift into R (Reverse), the rear wiper will turn on to intermittent if the front wipers are activated."

 

[Ephethean3]

From the manual: "When you shift into R (Reverse), the rear wiper will turn on to intermittent if the front wipers are activated."

Is that only if you have the auto sensing option? I don't and mine does run sometimes. I will have to experiment with putting it into reverse though to see if that causes it.

[plus 3 golfer]

Is that only if you have the auto sensing option? I don't and mine does run sometimes. I will have to experiment with putting it into reverse though to see if that causes it.

I usually don't leave auto sensing on but the times I forget to turn it off, I'm fairly sure that with auto sensing on, if I back out of the garage when raining, both front and back wipers come on.  As soon as you shift to D, the rear stops.   I do know that if in reverse and I turn on the front wiper for one swipe, the rear will also run one swipe.

[Ephethean3]

It was a nice rainy day today so I did some testing. I tested it each time I started out. After starting the car I would turn on the front wipers then while watching the rear wiper I put the car in reverse. Each time I did the rear wiper would cycle once. It wasn't in reverse long enough for me to see if it would cycle like it was in intermittent mode just like you quoted from the manual. I guess that I still can learn something new each day. Thanks for the info.

Edited August 12, 2017 by Ephethean3

[ptjones]

It was raining the day as I backed out of my garage and both front and back wipers were going as long as I was in reverse. During the day in the rain it happened every time in reverse. :)

 

Paul

[jestevens]

Switching to reverse when the wipers are "on" is the only time mine does that, it's actually a nice feature.  My car is always parked outside.  Maybe if you park the car in garage and leave the wipers on auto it's more noticeable when it tracks across a dry rear window?

[Bill-N]

I think it's a very nice feature.  To paraphrase the manual, when the vehicle is in reverse (and the rear wiper is turned "off"), the rear wiper operates in concert with the front wiper.