Central locking system

[amigaguy]

I have now installed the central locking system in my car. (More or less.)

The control box requires a ground "signal" when the door is opened, but I could only find a wire that gave +12V when the door was closed, and 0V when the door was open.

Thought it would be the opposite so that the 12V would power the ceiling light when the door was open, but no

I have solved this (sort of) by using a "inverted" relay which connects to ground when the door is opened. The relay lets the signal through when the power is cut (when the door is opened).

This is how I have hooked it up now:



It's not a good solution I suppose as the relay is consuming power when the door is closed and the +12V goes through.

The reason why the control box needs the ground signal is that it will lock the doors automatically if I accidently unlock the car and don't open a door within 25 seconds.

So... well it works now... sort of... the thing is that if I turn the lightswitch in the ceiling to ON, or OFF the doors open sign in the dash comes on :-D

If anyone has any bright ideas for how I can rewire this that would be nice :-)