Hakujin

When my car is locked, my car's factory alarm sometimes suddenly goes on/off without anything touching it. My interior light goes on/off by itself as well. I have just been keeping my interior light off for now, but I can't lock my car since I'm worried the alarm will go off! Has this happened to anyone before? Is it just a bad sensor somewhere? Any help would be appreciated.

mPod

I've had the same problem with my '99 over the past three weeks and had it at the dealer twice this week to fix the problem. They ran an SDS short test, some kind of diagnostic test, I think, and pulled a code out of the PSE (pneumatic system equipment) controller. They reprogrammed it and cleared the code. Didn't fix the problem but when I brought it back today they pulled the PSE and found corroded contacts. They cleaned the contacts on the PSE, replaced the connector on the harness and now I'll wait to see if that fixed the problem.

eclapton24

I have the same problem with the overhead light and with the alarm (occasionally just comes on when I press lock on the remote or try to lock with the key)...it's annoying so I'm taking it to the dealer next week.

Petmerctech

The problem is that water is leaking into the trunk because the weatherstripping is not sealing well. The water ends up corroding the PSE module contacts and harness and causes the alarm to trip on its own. You can either change the weatherstripping around the trunklid, or wrap the PSE module and harness in plastic to keep out water, or do both.

dinko

I was about to say...
I've been told that many convertible cars have leaks in the back. In the SLK however, the leak goes through to the Pump, which controls your alarm, lock, etc.

I believe it cost me about $400 or $500 to fix.