Club 80-90 Forums

Hello everyone.
My T25 immobilizer has stopped working but the van runs fine.
Normally if I try to drive the van with the immobiliser switched on. The van will start and I can drive OK for a few hundred yards then the engine stops. It won't start until I switch the immobiliser off. The immobiliser was fitter pre 2000.
I'm trying to work out how it originally worked. I found a large clear plastic relay connected near to the switch. But have no idea where all the other wires go from the relay.

I was hoping someone knows how these works with any wiring diagrams to explain it. Ta in advance john

If its an old one, bin it and start again. Pre millenial immo? They don't age well, Laserline were great BITD but now they are just a liability.

I am in the same situation, my immobiliser is broken and needs replacing, but this is new to me. It's this something that can be done by a talented amateur, or do I need to spend loads on it? Any recommendations for where to get one appreciated.

If it's any cop all the wires will be black.
To be thatcham approve then all connections should be soldered.
If you know what you are doing they are pretty easy to spot and remove.
Just follow the wires back from the immobilizer socket on the dash and you'll find the unit.
Usually just a case of chopping it all out and just connecting the original wires back to where they came from.
They'll have a battery live, on a VW that's usually red.
The earth's should be screwed to chassis, if they are connecting to original wiring that will be brown.
I should imagine that it'll need an ignition live, on VW that's black. They could have used black/yellow.
There will be some immo cuts to immobilise whichever system they are protecting, on a T3 then I'd say the starter will be one of them, those are a chunky red with a black stripe. Installers not knowing each vehicle inside out will probably have made these connections by the ignition switch
I'd say the other cut would be ignition, as above that's black or they could have immobilised the relief relay, thatd be the black/yellow above.
There's a remote chance they totally cut the power supply to the ignition switch, brave move as the internal relays and poxy 1mm wiring the alarms and immobilisers use is no way near butch enough for the load going through them and usually the downfall of an alarm and immo on a T3.
That is, unless I installed it then... good luck!