Greeting from So Cal where it’s cold right now (yes, we start *****ing around these parts when it drops under 70 degrees!).

I think I have a problem with my factory anti-theft system – or at least it’s not set correctly.

None of this took place until after I got the car back after the stealership fixed the harmonic balance that came flying apart. However, I had disconnected the battery with the key going on/off, and it seemed to stop the persistent clicking of the hazards.

Recently I changed the battery and the problem has come back, and I can’t get rid of it.

Here’s what happens:

When I turn my lights on, a “clicking” noise can be heard coming from behind the light switch. It also flashes the hazards, but no horn. It clicks/flashes for two “cycles”, lasting about 2-3 minutes.

Upon turning the lights off and exiting the car, it will go thru another cycle – but only after exiting the car.

I’ve also found if I place something in the change holder, it sets it off. Banging the stereo console sets it off. A hard bump sets on the road sets it off. Opening/closing the hood sets it off.

Reading thru the manual, it sounds exactly like the anti-theft is going off; the manual says it will go off for 2.5 minutes. But two things are not happening according to the manual – the horn is not going off, and the red light on the “locking” switch is not flashing.

So based upon the above – I think it’s the anti-theft – but how do I reset it, or disable it?

Your thoughts please and thanks in advance

Just a shot in the dark, but take the rear seat bench out and take a close look at the battery compartment. The PSE pump and rear fuse box live in there too. In addition to central locking, the PSE pump is also responsible for the Anti-Theft Alarm. If there's any water in there it may cause the problem you're having. Soggy PSE pumps are fairly common on SLK's, but I've seen a few 210's with the same problem. Let us know what you find.

Thanks for the response.

I too thought it might be the PSE pump, and reading about ot several years ago I inspected it and the fuse box and everything is in good order. I even placed a pice of heavy plastic over the foam to prevent any spilled liquid from taking the pump out.

I spoke with my brother, the former owner of the car. he said the dealer "upgraded" the "alarm" and it was tied into the factory anti-theft. However, both of us can never recall the alarm tripping, or even going off. I see a valet switch, but it doesn't seem to do anythiung, irrespective of the key sequence.

I'm a thinkin' there must be abrain box behind the stereo - and I will try to disable it, see what happens.

But I could still use some help and figuring out how to diabale the factory anti-theft.

Anybody, anybody.............

I've never tried to disable a factory ATA, at least on a networked car, but here's what I would try. Dis-connecting the alarm horn is simple enough, but you've still got to stop the lights from flashing. There's a signal wire between the PSE pump and the headlight switch which goes to 12V when the alarm is triggered. Try un-pinning this wire (PSE conn.4 -socket 1-YE/GN) and trip the alarm. Do this with the alarm horn still connected. If the horn sounds, but the lights don't flash, simply dis-connect the horn and you're done.

Make sure you check all other PSE functions when you're done. There shouldn't be any problem with RF locking/unlocking, but you'll obviously lose the "PANIC" feature.

Thanks for all the help ILUVMILS, it is very much appreciated.

Where can I find that pin - I looked on the PSA pump and didn't see it.

The panic, including the horn works (never tried that).

I also found a lead coming out of the firewall with two wires cut - looks like it could have been to a siren which is no longer in there. I also found a power lead jumped onto the positive harness at the battery - presumably for the alarm. I cut it, but nothing happened (car still clicked), so I reconnected it.

I'm convinced it's tripping the anti-theft, sans the horn, but the fact panic is working with the horn stumps me. I'm not that good with electronics.

Find the Yellow/Green wire at the PSE pump. That's the one you want to dis-connect. The horn issue may be related to version coding. If the car were in my shop, that's the first thing I would check. It's possible it may have defaulted to different settings when you replaced the battery.