Hi
I have a '98 SLK 230 Kompressor, the battery went flat (for an unknown reason, wife probably left the lights on) it was recharged, checked and replaced and now the alarm will not stop going off.

I unplugged the amp type connector to the alarm (a uk dealer fit at time of purchase back in '98 we we bought it new) and surprisingly the car still started and idled fine.
Unfortunately it doesn't drive very well forwards, as if it's badly 'missing' (oddly though reverse is fine) and plugging the alarm back in just causes it to go off continually until the battery goes flat again. it will stop sounding a little while after you lock the doors but immediately goes off again on re-opening them. Turning the ignition on or starting the car does not stop the alarm sounding. Neither does putting the alarm key (either the red or black one) in the socket for it.

Is there a set procedure to attempt to reset the alarm, plug it in with ignition on/off etc (a bit like on modern porsches) or is there a way to remove it easily without affecting the running of the car. Any wiring diagrams for the alarm connections or fault codes or other suggestions welcome.

Car is in good overall condition, no obvious earth wire problems - i've looked. it's done 100K miles

Thanks