Recently after about 15 minutes of locking my 2013 958TT with remote or on door entry my hazard lights have been flashing. I was able to replicate the problem consistently. I took off the pass side rear panel to access the Chassis Body Comfort Control Module which was clicking with the hazards. I purchased a used replacement module on Ebay and when I plugged it in the hazard lights wouldn't stop flashing no matter what I did using the keyless remote or turning ignition on etc. I plugged the old control module back in and my problem went away (temporarily im sure) BTW no matter what I do I cannot get the factory alarm to chirp on lock or blow any horn when it is set off. I've owned it for a year and never heard it chirp anyways. Anyone have any ideas?

 

If you are swapping out modules, you might have to code them to the vehicle with a scanning tool before they will work. And you'll probably need to scan the vehicle anyway to see what's going on with it.

 

it is not easy, replace and teach rear end ctrl unit. Should be online procedure @ dealer.
90% siren cause this problem. Connect new one for sure or code simle horn without backup power and forget about siren sound and hazard flashes.

 

This is interesting... Are you referring to this siren, located under the front wipers:



I have a 2013 Cayenne Diesel (US) and it has a metal disk siren in this location:



I was told at one time by a dealership that my vehicle shouldn't have that style/type, and I've always been curious why it did... Could it be that there was an issue similar to OP and it was replaced?

I purchased a used siren (first pic) to try and install, but haven't gotten around to it... Can I used this if wired properly?

 

chek by VIN, can PM me.

You can istall any siren if you like, but need proper wiring and piwis to change codings.

 

PM Sent... I appreciate the help.

I have a Launch x431 Pro Mini that appears to be a clone of the PIWIS, so hopefully that should work.

 

1K8951605A (last part number PAB951605) back up siren should be installed in you car, option 7AH.

you can install simple "disc", between ground and rear end unit output and code 7AC

 

Great, thanks for that info... I guess I need to tear into the vehicle and see what I can find...

Attached is a soundbite of what it currently sounds like, so I'm pretty sure it's got one of those "disc" sirens installed.

I'm not very familiar with the coding part yet, can you give me any info on where that section is located, or how to find it? Is this in the rear-end module?

 

Yes, you can check coding in rear unit.

 

Sweet, thanks!

 

The Launch scan tool appears to display things differently, but I think I found it:

 

looks like no back up siren coded. but better to check with piwis

 

I have a similar but different issue on my new-to-me '15 Cayenne S. Exterior lights come back on about 20 seconds after locking the car and they stay on. I made a detailed post on rennlist titled "Bought stolen 958 Cayenne with exterior lighting issue" but you seem to be the foremost expert on Cayenne sirens I've read on the internet haha.

PIWIS shows overhead dome lighting roof module is not communicating properly with rear end BCM. Wiring diagram shows what looks like two different alarms... one called "alarm siren" and one called "alarm horn". The C connector on my rear BCM does not have a BLK/VIO wire in pin 12 and I cannot find anything in the manual that suggests where I can find the "Theft-Protection Alarm Horn" in the vehicle. Is that the backup siren you speak of? My siren under the windshield wipers looks is 3-wire but I'm looking for the 2-wire.

Any thoughts or opinions you can offer here would be greatly appreciated. Is there a way I can look up the model number of every module that shipped with the car?
Maybe a previous repair attempt involved swapping out the rear BCM but with incorrect model number or it still needs online teaching?

 

once again. You would like replace backup siren with Alarm horn, simple 2 wires buzzer?
Not sure will this fix you lights trouble but it is easy to do. change pin on rear BCM and hook horn under panel. Code rear end, no online coding needed.

 

Thank you. I solved the lights issue finally... it was a grounded LIN communication wire.