E46 factory fit alarm sounding - all electronics dead
Hi, I hope someone can help. I've a 325ti SE Compact E46 with a factory fit alarm. The day before yesterday the alarm sounded without cause. I went to turn it off but found that all the car electrics were dead. No remote key operation, no lights on turning the ignition (although I think the air bag glowed dimly).
I pulled the negative off the battery. The alarm continued for a few minutes then went off. I put the battery on charge for about 8 hours but I'm not sure it needed it as the battery is only 5 months old and the charger needle didn't seem to move much.
Anyway, when I reconnected the battery the alarm sounded again, but this time when I turned the ignition the alarm went off and I had all the correct lights back on the dash. So all is well???
My question is, what caused it? Is it just the car electronics getting itself knotted up and my actions reset it and it wont happen again, or is it some electronic problem somewhere?