CD Player as an Immobiliser

[Mk III the HSV]

Hi all,

I was wondering if anyone had information on how to set up a CD Player as an Immobiliser ? There use to be a thread on this subject, but it was lost when JC suffered data loss a while back. Basically I want my car to be Immobilised, when ever the detachable face of the CD Player is removed. So if anyone has detailed info on how to set this up, it would be very much appreciated.

[SMIT]

I remember it being reasonable simple to do, should ask a mod if they can dig it up?

[Mk III the HSV]

Yeah, already tried that. They think is has been lost for good.

[kopper69]

Hmmm. Immobilising the car is the easy part, you just add a relay into a crucial circuit. Finding the signal here is the tricky part. You could take a signal from the remote wire. The remote wire switches on 12V when the headunit is there. If you were to turn the radio off or knocked the face and the screen disconnected while you were driving though, the car would turn off. You could take the remote signal and use it to trigger a circuit that is only used during starting, ie the engine circuit. That could work. It does mean that you will need to wait a few seconds for the remote signal to come from the headunit (typically about 2 seconds) before the car will start.

[garfa]

Hmmm. Immobilising the car is the easy part, you just add a relay into a crucial circuit. Finding the signal here is the tricky part. You could take a signal from the remote wire. The remote wire switches on 12V when the headunit is there. If you were to turn the radio off or knocked the face and the screen disconnected while you were driving though, the car would turn off. You could take the remote signal and use it to trigger a circuit that is only used during starting, ie the engine circuit. That could work. It does mean that you will need to wait a few seconds for the remote signal to come from the headunit (typically about 2 seconds) before the car will start.

depends on the circut you cut.
if its the acc/on wire/s then yes there could be problems but it does recommend NOT to cut the ign circut in most alarm manuals.

put the interupt in the starter wire.

but remember that if you have a big relay there the thief will just trigger it. be a bit more creative and use multiple smaller black wires and have the relay a bit more hidden.

[woteva]

If you were to turn the radio off or knocked the face and the screen disconnected while you were driving though, the car would turn off.

Just use a diode to keep the relay powered up, even if the radio is turned off while driving. Just run the diode from the cold side of the relay to the positive side of the switch to keep the relay on.

[SweetWagon]

I think the easiest and best interupt would be the inhibitor/neutral safety switch. It is simply a switched earth so if its not earthing = no start. not sure about later models but i beleive even manual models have this feature in the ECM but its constant earth. You would just need to find this wire on the ECM and put your relay between it.

[kopper69]

I think the easiest and best interupt would be the inhibitor/neutral safety switch. It is simply a switched earth so if its not earthing = no start. not sure about later models but i beleive even manual models have this feature in the ECM but its constant earth. You would just need to find this wire on the ECM and put your relay between it.

Good point mate. Circuit only comes into play during start and wouldnt carry much current at all, mainly a signal. Once the car is running it doesnt worry about it at all.