Cayenne Odd Alarm Issue!

[Simon Ambrose]

I have an issue with my 2007’s internal ultrasonic sensor. When I lock the car the door LED flashes and then stays on as if I’ve pressed it twice when I haven’t, and the car has been broken into twice and the alarm has gone off zero times annoyingly!!

 

i have tested the sensor at roof level and it’s getting 12v and doesn’t look wet or anything. I’ve even swapped it for another unit which made zero difference. It’s as if it’s been disabled in the ECU or via the door pillar button which in any case isn’t there at all on my model. The computer menu says it’s checked so it ought to work. Apparently it shows a fault code when on diagnostic, so I’m guessing it could be the actual alarm module, which is under the E-Box if I’m guessing right??

 

Has anyone had any experience with pulling this out and changing it? The alarm still works on the bonnet (leave it slightly open and then open it after setting, and it goes off). So it’s semi working. I’m guessing maybe a wiring issue somewhere on the signal return side if not the power side if it’s not the module itself. All advice appreciated!!

 

thanks

 

simon

[JFP in PA]

Welcome to RennTech 

Replacing that module will require coding the module with a PIWIS unit.  I would suggest getting the system scanned with a Porsche specific diagnostic tool, looking at the alarm system codes to point you to what is faulting before doing anything.

[Simon Ambrose]

Thanks for your reply. I had my independent garage scan the code and it pointed to general fault and they couldn’t tell me whether it was the module, the overhead sensor or they said also the module in the rear boot, which I didn’t know also controlled the alarm?? Is this true?