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wiring help needed x20xev

Nov 18, 2008
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Hi there everyone just wonderd if any one here clever enough to help with a problem i have come accross.

I have a mk4 astra 1.6 8v that has had a x20xev vectra engine put in all the engine loom as swapped accross from the vectra to the mk4 and also i have a transponder and chip for the matching ecu that came wiith the vectra.

In the past i have put c20xe's and c20lets into nova and corsa's and mk3 astra even 2.5v6's into astra's so i am pretty clued up on this type of thing not saying im the best.

The problem i have is getting past the immobiliser on this one as the plug that go into the back of the transponders differ from the 2 models.

The astra one starting from the left working accross
pin 1. purple and brown pin2. brown and blue pin 3. blank pin 4. brown pin 5. black pin 6. brown and white pin 7. brown and white pin 8. blank pin 9 red.

Now on the vectrastrarting from the left.

pin 1. purple and brown pin 2.brown and blue pin 3.blank pin 4. brown pin 5. black pin 6 blue and red pin 7. blue and black pin 8. brown and white and pin 9. red.

So they all the same up to pin 5 then it goes a little out of control

I know the obvious wires like the red live the black ignition the brown earth green rev counter brown and white brown and yellow brown and blue diagnostics blue temperature.

I did a continuity test on the original mk4 transponder plug and come up with from the back of the transponder that pin 9. is a thin red and goes to the old ecu plug, pin 8. blank, pin 7. brown and white goes to the plug on the hold ecu, pin 6. brown and white goes down to diagnostic socket pin 5. black goes to the old ecu. pin 4. brown just prosumed earth to any other brown pin 3. blank pin 2. brown and blue to old ecu plug. and pin 1. brown and purple couldnt find but after searching the net someone says to alarm.

Now as the plugs differ in wire colours i took the one from the vectra to wire in the astra so as the pin 1 - 5 are all the same i did them colour to colour

Pin 6 is red and blue witch i prosume as the wires coming from the ecu as the same thickness blue and red these join so pin 6 blue and red to thin blue and red from the ecu pin 7 blue and black also as a blue and black from ecu so joined them together pin 8. brown and white ive tried both to a brown and white coming from ecu wires and also down to the diagnostic plug. and last but not least pin 9 witch is a red but there is no red coming from the ecu plug so i have put a live feed to the red on the transponder as i think as it went to the ecu before the ecu run the power to the transponder.

But after all this i am wrong as the engine managment light just flashes. I know that if you have one of these cars with this fitted you can take the chip from the key and tape it to the transponder and it will run so i taped the chip to the transponder and just tried wiring it up at the side of the ecu so i missed all the other wiring out and still got the same problem.

Does any 1 know how i could just wire the transponder to the ecu as if i put this engine into a nova i would have no wires around the ignition barrel and would need to wire the transponder from scratch to me this would be a lot easier if some1 knows the way to wire this up alone and me just leave the mk4 original wires out the loom.
if anyone can help i need to know what the 8 wires from the transponder go to on the vectra set up as follows.

pin 1. brown/purple tracer =___________
pin 2. brown/blue tracer=___________
pin 3. blank= blank
pin 4. brown = ____________ i prosume a earth
pin 5. black = _____________ i prosume ignition live.
pin 6. red and blue = ________ i prosume speed signal
pin 7.blue and black =___________
pin 8. brown and white =______________
pin 9. red = _________________

if any one as any info i would be more than happy to here it thanks goin now cos took that long to write my heads up my arse but will keep adding thank
even a wiring diagram and no haynes or auto data do not cover the wiring for transponder in either the mk4 or the vectra manual.

Please excuse my punctuation as cars was more importent to play with than go to school as normally every website i been on people love to bitch about capitals and full stops but when there aint enuf hours in a day i ant got time to be stoping.

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