SLK200 R171 (2006).I am a new member, and have a problem with locking the car from either remote fob. It will not lock/unlock. The remotes are OK (red light flashes on operating the buttons. The car will lock/unlock from the buttons on the dash. I have checked the fuses for anti theft alarm (8,22,37) and central locking (15,27,28,37). All OK, except No. 8 (antenna booster) in the boot behind a trim panel, this one was blown, and keeps blowing on replacement. I am assuming a fault with the booster, but can't find where it is. Can anyone help me please? Is this a known problem, and will it be expensive to fix? I am a fairly competent mechanic, with a basic knowledge of electrics, I have done a lot of restoration work on old cars, but not a lot on the modern stuff.
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Trigger the car alarm to see if it works.
It should sound for 30 seconds and the hazards should flash for 3 minutes.
If you can’t lock the car with the remote in the usual way, try holding the end of the remote a few mm from the sensor on the door handle and press the lock button.
Dec
It should sound for 30 seconds and the hazards should flash for 3 minutes.
If you can’t lock the car with the remote in the usual way, try holding the end of the remote a few mm from the sensor on the door handle and press the lock button.
Dec
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Car locks/unlocks fine with remoteclose to door handle. I set the alarm with the window down, leaned in and opened the door, horn did not sound, hazards started, but did not stop after 3 minutes. Had to switch it off after 5 mins.
That alarm fault probably has something to do with the locking problem.
Best to unplug and remove the siren from the car, you can replace with a new alarm siren from an MB dealer for about £100, if you fit it yourself. Re-check fuses again after you have dealt with the alarm siren.
I think it’s located behind passenger side wheel arch liner, see here… https://www.google.com/search?q=r17...UICigB&biw=1274&bih=891#imgrc=AZQj9jsvg6ib5M:
Dec
Best to unplug and remove the siren from the car, you can replace with a new alarm siren from an MB dealer for about £100, if you fit it yourself. Re-check fuses again after you have dealt with the alarm siren.
I think it’s located behind passenger side wheel arch liner, see here… https://www.google.com/search?q=r17...UICigB&biw=1274&bih=891#imgrc=AZQj9jsvg6ib5M:
Dec
After removing left front wheel arch panel ( no siren )., I found the siren hidden behind the battery ! Replaced it (£30 from breakers) - no change !
Found the aerial booster behind trim panel in the boot (beneath the aerial). Replaced it
(£96 from breakers), job done- all working well, including alarm siren.
Many thanks to 'Dec' for your thoughts and guidance.
Found the aerial booster behind trim panel in the boot (beneath the aerial). Replaced it
(£96 from breakers), job done- all working well, including alarm siren.
Many thanks to 'Dec' for your thoughts and guidance.
Codger49
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Pleased to hear you found and fixed the aerial problem.
MB sirens have their own internal batteries mounted on the pcb. The problem with these is, that after 10 years or so, the internal batteries corrode and effectively ruin the pcb.
Breaker sourced sirens thus will give you only a short term life, hence Dec's recommendation above to source a new siren.
Some people have cut their sirens open and, if the pcb is still usable, resoldered new batteries on the pcb. You will find a few threads on this repair around.
MB sirens have their own internal batteries mounted on the pcb. The problem with these is, that after 10 years or so, the internal batteries corrode and effectively ruin the pcb.
Breaker sourced sirens thus will give you only a short term life, hence Dec's recommendation above to source a new siren.
Some people have cut their sirens open and, if the pcb is still usable, resoldered new batteries on the pcb. You will find a few threads on this repair around.
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