Intermittent issue with trunk and back windows opening on their own

BIONDOLILLO CARLO

MEMBER
2008 VOLKSWAGEN PASSAT
1.9L
4 CYL
TURBO
2WD
MANUAL
175,000 MILES

Trunk and back windows open while the car is parked and no key in. A very intermittent problem sometimes after a week others after 6 months. VW has diagnosed the problem many times without conclusions as they could never see the problem. 90% of the times trunk and back windows open, 10% of the time only the windows. Any clues? I am helping my brother and this is driving him crazy. Thank you!

Wednesday, August 19th, 2020 AT 11:35 AM

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

This is most certainly one of two things. First either someone is messing with him rolling the windows down and popping the trunk or you have a short to power in the wiring. The odd thing is, the rear windows and trunk have nothing in common other then the driver side door control module. If you look at these wiring diagrams you will see that the DDM has input to both rear windows and directly controls the trunk lid release.

Clearly this is a guess as we would need to perform some testing while this is acting up but it is so intermittent that this would be nearly impossible.

If you want to guess at it, I would put the driver door control module in it and then if it never happens again, it was either the issue or a coincidence.

Let me know what questions you have. Thanks

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