Porsche Cayman 981 gts alarm fault

[paulo16]

hi, iv been bugged by an alarm fault with it intermittently going off, also chirping when locking as if something like a door
glovebox/trunk/boot was open

after me replacing the rear boot catch and swapping the alarm over with a 981 boxster I still had the fault

so its been in to porsche and they said I had a rear windows breakage sensor fault
and the sensor was in the glass, so I had national windscreens come out and they said there's no sensor in the old or new and to not bother and get it back into porsche, so off it went back to porsche and they again confirmed it would need a new rear glass as the sensor is in the
heated element and are telling the control unit there's a break in the glass hence the alarm going off.

so last week nation windscreen came out and replace the glass I no longer have the chirp and the alarm has not gone off since.

I wrote this up in case it helps anyone, I found nothing on the forums about porsche window breakage sensor apart from a cayenne which had
an actual sensor on the glass.

cheers Paul
2014 cayman gts

 

[Motorhead]

That’s a weird one! I would imagine that only a PIWIS or similar Porsche-specific analyser would pick-up that fault.

Was your rear screen heating element working?

Jeff

 

[paulo16]

yeh for sure I think only main dealer diagnostics would find that, the heated rear screen did work although I only got the car 6 weeks ago

so couldnt test it fully as missed out on the snow with this car, I did notice the glass had lots of breakages in the glass heated elements

but never thought that would also interact with alarm circuit, maybe if the glass has to many breakages then it triggers it

all I know is the windscreen people have never come across it before but then again rear window replacements prob alot rare to windscreens etc. cheers