Hi, my alarm goes off when driving and I cannot switch it off unless I pull the fuse! My car is a red coupe registered December 2003 with 60k miles. I've had the car for 9 years and never experienced this before.
Can anyone help with this problem.

Regards,

Gary

 

possibly a battery on the way out?

 

Hi,

first check in the boot under the foam plastic to make sure its not like a swimming pool. If that checks out OK then its the alarm siren causing the problem.

Does the alarm go silent when you pull the fuse?? if so it means the internal battery for the alarm sounder has failed, its probably leaked over the circuit board causing the false alarms.

As a stop gap you can disconnect the alarm sounder ( instead of pulling the fuse) as that way you can still lock the vehicle and set the alarm but it wont make a sound.

The alarm siren itself is under the lower windscreen trim where the wipers come through. its just on the passenger side!

There is quite a few threads about removing it and also possibly replacing the battery. My alarm started doing the exact same thing 4 weeks after buying it, it spent a week with the alarm disconnected without problems and after replacing the internal batteries its been fault free for the last 12 months.

found one of the threads https://www.crossfireforum.org/forum...d.php?p=770974


Matt

 

Thx for the quick replies guys. I've had the battery checked and its A ok. No water in the boot under the plastic either so it sounds like its the batteries in the alarm! Will have to find someone with the necessary tools to do the job asap. Thx again

Gary

 

I had the same problem,

Changed the battery, but that had no effect.

Then changes the sirene for the newer type wich also had a beep for open/closing the doors. And that fixed my problem.

If u need the partnumber i bought at Mercedes let me know!

 

You might be able to get the siren out without removing the wiper arms. I did, after removing the screw's along the front edge. Unbolt it from the bulkhead and wiggle it out then unplug the connector. I had to do it this way as it was driving me and the neighbours mad late at night and I couldn't lock it with out the fuse.

When I priced up a replacement at MB they had quite a few on the shelf as they class them as consumables.

Usual disclaimer, the plastic didn't break on mine and it's a bodge! Try doing it this way at your peril!

Matt

 

That would be great if you could supply me with the replacement Mercedes part number if I decide to replace the Alarm!

Regards,

Gary

 

Took me a while to find the receipt.
A 2198203226 That's the one i bought. Worked great for me fixed my problem instantly. This is the one with the Beep for locking/unlocking the car.
Bought it for € 86,87 Excl VAT. Bought at a local Mercedes Garage/dealer.
Had my regular garage put it in for me since it had to be there for M.O.T.

Also i found that i had more problems with my broken alarm when it had just rained the other day, don't know if u have the same symptons when wet outside.
Let me know if and how u fixed the problem

 

So my alarm goes off lately when it sits.lights flash but super weak to no siren sounds. Today the doors would not open with the remote and doors will not unlock at the dash either. The lights flash every time I open doors or the hood. Worst aprt, the engine won't start. I pulled fuse #9-roof light, horn, antitheft, trunk light, etc. that is to the brake booster. The horn still works and the alarm continues. What fuse stops the siren?
Sure hope someone is online. I am stuck at work

 

You had better post just one request not two, I answered the other and what you say here is different to what you said in the other one. If you have two threads going the answers in both may be totally different.

 

When i had the same problem i disconected the battery for a few minute's then wait untill the alarm goes completly silent. Then connect the battery again. This should give u a few miles before the alarm maybe activates again.

Replacing the alarmhorn probably is the fix to your problem

Good luck,

 

That fixed mine to. The later siren that's beeps on lock etc.

 

So glad the forum is here. I did not find the answer about disconnecting the battery until I spent two hours going through other suggestions then giving up and got towed home. At home I found the suggestion to disconnect the battery to reset the alarm. That worked. Wish I could have found it before having the tow. I ran without setting the alarm until the new siren arrived and I had time to install it. Old Part Number: 5124443AA (replaced by newer version AB) New Part Number: 5124443AB Part Name: SIREN ALARM MSRP$185.00
The beep when setting the alarm with this unit is not offensive as others suggested, it is pretty quiet. Everything works fine with this siren replaced. glad it was NOT the SKREEM as the dealer quoted $900 to replace that!

 

Good to hear the problem is fixed

 

Also happy it's fixed, however a new set of batteries for the old alarm is @ $30 US.

https://www.crossfireforum.org/forum...rm-module.html

 

I'm still puzzled how replacing the alarm siren had an effect on the door locks, especially the fact the Central Locking button on the dash was inoperative as well. After reading a ton of threads I would have suspected several other items, from fuses to the vacuum pump in the trunk, etc.