Hi all, 1st timer here, be gentle ok so ive got massive problems, car hasnt started for couple months, just stopped starting out of the blue no warning signs. Mechanic couldnt connect to ECU but said that I had spark and fuel for 2 seconds then cut out which indicated immo problems . Sent the ECU, coil reader thingy, immo and keys away, they couldnt talk with it either so bought a second hand ECU and thought about mating it up to my immo using a flleabay cable. I have tried with a 2nd ECU, ive tried with old release VCDS, checked the K-line, power and ground at the port seem to be fine but not been able to connect with my original ECU or a replacement ECU. I haven't got a k-line wiring diagram but I have been able to trace the k-line to the immo but not to the ECU (or radio for that matter). T68/43 ECU connector is listed as the k-line data connector (for volkswagens...) but from what ive been able to test on my car it isnt...wire that comes from pin 43 is a green wire that goes to the immo (output signal from ECU?) but is not the grey/white k-line wire from the diagnostic port. Also I cant see any grey/white wires at the loom going into the ECU and a continuity test from the port to the ECU connector yielded nada..whereas ABS connector does have a grey/white k-line. Im stumped...Can anyone shed any light on whats going on? car is a 99 Seat Ibiza 2.0 16V
yes the k-line on immobilised cars goes direct to the immobiliser box, then there is a diagnostic wire from immob box to the diagnostics jumper block which both the ecu and immobiliser box talk down. can you speak to the immobiliser box at least? if not then this is probably why, either the wire to the box is damaged or it isnt powering up due to a lost ign live or live feed. see my sig g3immobiliser98on.pdf for a diagram for your immobiliser box
no I cant talk to immobilizer either. Thanks for that found the junction block the bottom pins on it are: green/red wire (immo K-line) grey/white wire (k-line abs ?), plug with 2nd grey/white wire with yellow wire on top (from diagnostic port) and a 3rd grey/white wire (k-line airbag?) with 2 sockets to spare. No sign of that green diagnostic wire though, your schematic shows it as going to the ecu via T1 - single connector behind the relay plate..does that mean it should be taking up one of the spare sockets on the block? and what does that yellow wire do? cheers
the green wire on the seat loom goes straight to the immob box thats what it is, on mk3 there is a single pin plug inline with it which is just floating about back there. the fact you cant even talk to the immobiliser would suggest a wiring fault between the jumper block and immob box, or the immob box itself is bust. if you unplug it you can bridge a wire between the ecu green wire and the diagnostics jumper block green/red, if you can then talk to the ecu you have an immob box fault, if not its a wiring fault
I had tried the day before to bridge the k-line to the green at the immob without success but tried disconnecting the immob as you said - win! connected to both ECU's and have the immob blocking engine start code on VCDS. Faulty immob seems to be, I ordered a immob emulator last week just in case I wasnt able to connect with ECU so I could bypass the whole ECU-immob mating thing, seems like its the solution of all my problems. Time to put my car back together...Your a legend mate, many thanks
