Hi guys,

My '99 996 C2 Cab alarm keeps going off for no reason. Three times in a row at Lowes (within 5 minutes), then it was fine for a couple of days, then 3 times last night at home until I decided to leave the doors unlocked. I've been driving the car around all day, and the alarm just went off again in my driveway.

When I lock the car, I do *not* get the beep, meaning that everything is fine. I'm a bit a confused and don't really know what to look for.

I recently took the calipers off, painted them and changed the pads and brake fluid. I don't see how it could be related but the timing seems to be pointing in that direction.

Thanks a lot!

 

I'm curious what the alarm sounds like. I had a '99 Cab C2 for 7 years, have a Boxster going on 11 years and have a 996TT Cab. Never heard the alarm in any of them.

 

Try double locking it to turn the interior motion off. That way you can atleast see if that might be setting it off.

 

Nick49: The alarm is just the horn going off over and over.

OP: if you have a Durametric/PST2/PIWIS you could read the alarm history and find what is setting it off.

 

I don't have one of those. I guess it's time to go see a Porsche mechanic.

Anyone knows if it could be related to me lifting the car or to new brakes/removing calipers or any of the things I did?

 

shot in the dark.
On my A6, the connector for the hood sensor had corroded and would cause the alarm to go off, especially on rainy days.

 

My 99 996 does the same thing. I do the double lock as suggested earlier, and that does the trick.

 

You don't happen to have a windshield sun deflector that you use to keep the sun out? That's the only time my motion sensor causes a false alarm.

 

Problem got worse. I can't lock the doors anymore. A couple seconds after I lock, I get "beep beep" and the doors unlock themselves. Really odd...

 

Same thing happened to me recently, car would lock normally with two blinker light signal but alarm will go off automatically after several minutes. Apparent caused was an unlock frunk. Closed it properly and problem solved.