Unusual Rear Wiper Blade Problem

[djpg2000]

First of all, my rear window is all the way up. Please read carefully because I have searched the forum and am unable to find a thread regarding this specific problem.

Description of Problem:

When I turn my rear wiper on, it starts to move and then stops in the middle of the window and stays there until I unplug the ECU in the tailgate and plug it back in to reset it.

Functions That Work:

- Rear window
- Rear defroster
- Rear windshield washer fluid sprays at first but causes wiper to move which triggers the problem above.

Functions That Don't Work:

- Rear electronic door handle to open the tailgate (unsure if it's related)

Possible Solution:

I'm thinking of replacing the ECU and hopefully that will fix the problem. Any ideas or suggestions? Thanks in advance!

 

[TRUSTYAXE]

Replacing the ECU sounds kinda hardcore to start your troubleshooting. I believe there is a switch that confirms the rear window is up all the way. Maybe remove the panel for access, clean some contacts and ohm it out.

 

[djpg2000]

Fyi, I already sprayed all of the contacts, as well as the inside of the ECU (yup, I took it apart), with contact cleaner. Anything else you can think of?

 

[nglayton]

I believe there is a switch that confirms the rear window is up all the way.

I think if the window wasn't up all the way, the wiper would not go down to begin with.......

I have no clue how it's designed, but I would start with the wire harness and the motor before the ECU.

 

[djpg2000]

I guess I'll just start taking stuff apart and seeing what I can find. Anyone else have any other suggestions?

 

[4RnR Grl]

I guess I'll just start taking stuff apart and seeing what I can find. Anyone else have any other suggestions?

Take apart your center console (around the shifter (video in my thread)). Everything runs through there. Check every connection and make sure nothing is corroded, loose, etc.

Sent from my SAMSUNG-SM-G930A using Tapatalk

 

[scanny]

I think that logically there should be some sensor limiting move of the rear viper, something that tells it do not move when it has too much resistance. I might be wrong since I have no idea what I'm a talking about but I would check for debris, ice or wear around wiper, maybe try to find a way to disconnect it from motor and try move it manually.
Another my idea is that since wiper starts moving before it dies - something happens on the way, probably due to vibration some sensor thinks that rear window got opened just a little or electrical contact in the connector gets loose.