JJL742

ALARM NOT WORKING AND ALSO PANIC BUTTON ON FOB
2005 CLK 320

Rudeney

Check fuse #8 (panel in the trunk). It controls both the ATA siren and the remote functions of the key fob. If it's blown, and a new fuse also blows, then you likely have a bad ATA siren and will need to replace it. If it's not blown, and remote locking works, then it's just the ATA siren. It's fairly easy to replace - it's behind the passenger front wheel. Just remove the plastic fender shroud for access.

hpuxsux

Hi,

I just stumbled across this thread. I have a 2005 CLK55 that I purchased a few months ago. From the day I bought the vehicle when I locked the car the alarm would make the weak beep like when the alarm battery is dead. My 2004 C230 had that issue, so I am familiar with the sound. Anyway, I replaced the siren today and went to test with the panic button. It failed no sound. I locked the car and tried to trip the alarm, again nothing. I checked fuse number 8 on the rear SAM, the fuse is good. It still makes the same beep as if the alarm battery is dead. Any other suggestions on where the issue might be.

I know the previous owner removed the original radio and installed a nav unit. Could this cause this issue?

Any suggestions would be appreciated.

Rudeney

Hi Gene,

Where did you get the siren? Is it a new genuine MBZ part?

hpuxsux

Yes, Sir!

It is a Genuine Mercedes Benz replacement part from the dealership.

Regards,
Gene

Rudeney

When you press the panic button or trip the alarm, do the lights flash? If not, then it's not the ATA siren causing the problem.

hpuxsux

I tried both keys. There is no repsonse (lights or siren or horn) from the vehicle when I hit the panic button. It looks like there are a control module and four senors associated with the ATA, could one of these be bad?

Regards,
Gene

Rudeney

There is no single ATA control module. It's a combination of various components. I think the main controller is the rear SAM, but the ATA siren is also involved. If you roll down a window, lock the car with the SmartKey fob, then reach in and open the door, do you also not get any lights flashing? If that does work but the panic button does not, then that would indicate a problem in the antenna receiver for RCL. If opening a door does not trigger the alarm and flashing lights, then I suspect a problem in the SAM, but that would require some hands-on investigation with SDS.

hpuxsux

Rudeney

I think you have a problem with the rear SAM. I'd get a scan tool that can check it - SDS, iCarsoft MBII or i980, or Autel MD802 Elite.

xrayok

Alarm and remote entry was never working, so I checked the #8 fuse and it was blown. Replaced it and remote entry would only work occasionally - one in 10 or 12 tries. Unhooked the alarm behind the wheel liner and now the remote works reliably. It also seems to have cured my weak FM radio reception and hoping it may cure the battery drain on my 2005 CLK55 convertible. Appreciate the tips from fellow car enthusiasts.