Here's my problem...the alarm I installed in my car has never worked properly. It's old, Alpine 8040, and I wired both an impact and a glassbreak sensor onto the same "optional" input. When the alarm goes off for no reason, it flashes the code for this sensor. I was told that they are feeding off of each other, tripping the alarm, and that a few diodes should solve this problem. I did one hell of an install and everything is so well hidden, (both in my car and my memory), that I really don't remember where everything meets up. Both sensors have red wires(power) and black wires(ground, I think). They each have a third wire that I'm guessing are the ones I fused into the "option" wire of the alarm itself. Does this sound right? If so, the diodes should go in-line on this third wire, cathode towards the brain, correct? I really hope someone has some advice on this....thanks.

 

You have to use 2 diodes, one for each sensor. You need a diode to isolate each sensor, otherwise, you will get false alarms or erratic behavior. This way, if the alarm triggers, you will be able to tell which zone caused the alarm. I hope this helps.