Rear Glass Break Sensor - Alarm triggering randomly. Dealer refuses coverage

[COar]

When I bought the car a year ago, the PPI discovered a "Rear Glass Break Sensor Fault". It seemed minor and I paid no mind to it until about a month ago. Between maybe once a week to every few days, the alarm will go off without any apparent outside cause.

Since the car has an extended warranty, I took it to the dealer today to diagnose. They refuse to address it - first saying the car was maybe damaged, then saying the window tint installation may have affected it. The car has never been in an accident so the first one is out, 2nd explanation is plausible.

Based on my googling, the glass break sensor fault is not a common occurrence, but could the sensor realistically be caused by 3rd party damage, or is the dealer trying to pull wool over my eyes? The other possibility is tech is just inexperienced - according to his Facebook he was parts driver just 2 years ago so his wrenching time seems limited.


The last part might also be why he chalked up my transmission low speed harshness to my taller winter tires (215-65-17), despite this harshness being evident well before I installed them...but that's a story for a different day.

[colorado.a4]

Audi won’t warranty parts if there is any outside influence that could be a causable reason. It’s not just the technician that decides if it’s warrantable, but Audi’s warranty department.

I have to decline warranty work on a lot of cars due to this and while unfortunate, it’s just how warranty works. I suppose if the dealership is willing to over look the tint then it’s a possibility but that’s a small percentage of dealerships.

[Smac770]

https://www.audizine.com/forum/showt...or-Where-is-it

So you're just looking for a "wire" that runs from the J393 T32d pin 21 through the rear glass, through the right rear glass, through the left rear glass, to ground. So there will be a two pin plug two each of the three glass pieces. Somewhere you will detect an open circuit. If it's the glass, then you're replacing the glass. If it's the wiring between the glasses, then you're replacing that. But there's no intelligence, no logic, simple wire path that is broken somewhere. You'll probably have to pull the rear lid trim and the cargo space side panels to get to the plugs.

But if it does turn out to be one of the glasses, yeah, good luck on the sell with that aftermarket tinting. You can clearly feel the orange lines for the antenna on the inside, but I can't be sure where the "G183" and "G184" wiring is actually running; is it under the black tint, e.g.

[COar]

So apparently the service advisor never even contacted the warranty provider to see if this would be covered. She called them up yesterday, and lo and behold, everything was covered (sans the tint, which is only ~$35 out of pocket). The issue was the alarm wire was corroded. They're replacing the entire driver side rear corner glass. The warranty also covered the transmission reset. Pretty pleased again with the service from Flatirons Audi.

They put me up in A5 Sportback Prestige loaner with 3k miles. That's a great marketing tactic - my B8.5 is only 6 yrs old but it feels like a dinosaur compared to the new cars.