That wire you have there needs to be connected to the engine loom. There will be a correspondingly colored wire behind the fuse box.... (grey with white stripe.) they wont connect in to each other because in a mk3 the wire from the engine loom (goes to ecu), wire from immo unit (the one you have there) and the one for the diagnostic socket all connect into a little plastic splitter box effectively joining all the signals together. (k-line)
Locate all three grey/ white stripe wires, connect them all together (solder is easiest.) Hey presto, working immo, working car.
