BMW Repair: alarm resetting, sensor light, alarm systems

Question
hi having just fitted a new battery I seam to be having problems resetting the alarm I have tried turning it off /on with the key but the sensor light will no go off and the alarm sounds when I start the car or open a DOOR .
I LOOKED IN the hand book but it says I need a magnetic key? I don't have that? car is a 318 lux 1991 h (uk)


Answer
Caroline,
 Is it a FACTORY alarm or an aftermarket unit that someone installed.  
 I have never messed with factory alarm systems on the BMW's.  Since the only option is to use the "magnetic key" looks like you need to contact the dealership to find out what is needed.  Unfortunately I cannot help anymore with this matter, looks like you need the key, or to have someone disengage the siren/horn so you can drive it to get it fixed.

 Hope this helps,
 Josh