W202 2000 c280 ALARM / LOCKING PROBLEM

[grahamcol]

Hi,
My car suddenly started playing up. If I press the lock button, the alarm sets itself (flashes / blips) but then immediately the interior lights turn on and the indicators flash like mad. No alarm sounds however. If I then press unlock and open the driver's door this puts out just the front interior lights and the indicators stop flashing. The rear interior light remains on for a while and sometimes upon opening the door the alarm sounds (even though it is supposedly switched off from the remote button). I've tried disconnecting the battery for 30 mins and this seems to fix the problem until the car is next driven when it plays up again. Any ideas please ?

 

[bigasotonuk]

Hi,
Welcome to the forum.
In the first instance I would check your door/boot/bonnet pin switches for correct operation as it seems the alarm when set is seeing an alarm condition immediatly it goes live.
But the alarm sirens themselves do suffer from water ingress and knackered internal batteries causing similar faults that you have described.

 

[grahamcol]

Thanks for this reply. I've just done all that but no difference really. Got it booked into my indie for Thursday.

 

[grahamcol]

Update. My Indie (WDM Cars, Birmingham) put it on Star and it threw up faulty rear door switch and faulty siren. They replaced switch and by-passed siren and alarm now sounds with the horn rather than siren. I have the option of having siren replaced but might not bother. WDM are very very helpful and the owner, Wayne, hasn't even charged me yet, preferring me to test the car for a few days and report back. I've been there before and I cannot recommend them highly enough.

 

[bigasotonuk]

Hi,
Thank you for posting back with what was wrong.
I,m pleased you got it sorted.