R129 Alarm ?
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Old Merc

Original Poster:

3,802 posts

191 months

Saturday 10th May 2014
quotequote all
When I tried my spare key (its been in a draw for a year)the doors unlock,the red AND the green lights in the mirror flash constantly,the car STARTS? but the alarm goes off?? I can not kill the alarm with that key? I then use my regular key and its all back to normal and working perfectly.
I suppose the spare has lost its memory or what ever?? any suggestions Merc experts.
Its a SL320 1997.




mickyveloce

1,035 posts

260 months

Saturday 10th May 2014
quotequote all
Swap the battery from the everyday key to the spare; I suspect the battery in your spare key may be u/s.

The whole red-green flashing light thing can be a pain. In the case of my 96 C36, the car kept immobilizing itself and I ended up having to take it to Merc to replace the transponder.