mk1 20vt wiring HELP ME!

Hi folks, got a 1986 mk1 golf cabby, got a 1.8t 20v AGU from an audi a3 1999 auto, started the wiring in today all went well til i tried to start it lol…. ive had the ecu coded to NOT need a transponder to work! had this done by "duplicute" cost me 50 quid, the guy told me it is now in run mode…. basically i can get  power to all the engine sensors/coils and injectors BUT i am not getting any earth outputs from the ecu. from the diagrams pin 4 on the ecu is a NEGATIVE ACTIVATION to the main relay..i am not gettin this, i think the ceu is still imobilized… ther are still a few wires i have not connected for example gearbox signle ,clock wires etc….  can anyone help. im so close lol….  how can i test the ecu, or shouldf i just take it back and askn them to test. any feedback would be great…..cf_emoticons__BangHead:cf_emoticons__BangHead:cf_
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even if immob cut in im pretty sure the car will start for a few seconds then cut out. best bet is get your diagnostics wired up then you can see if the ecu is even powering up ok. pin 4 is the earth trigger for the fuel pump relay, there is no ecu relay on the agu if thats what you meant?

important wires are:
1 - main ecu live
2 - earth
3 - permanent live
4 - fuel pump earth trigger
6 - rev counter (need adaptor)
19 - diagnostics
67 - sensor earth

its either dead or your doing something wrong.

I killed my first ECU, similar problems to you.

got a second one from ebay, the car turned over and sparked etc, then got it deimmobilised and it works ok

thanks for the reply, got all the correct power supplys and earths double checked! definitly got no earth trigger from pin 4 to activate fuel relay! when i switch the ignition key i can hear a f ew things clickin and buzzing, i know that dont mean much, but i reckon the ecu isnt demobilized correctly. looking at the Audi a3 diagrams pin 4   activates the main relay which also puts live power to injectors and coils etc..got it all cranking and stuff. this agu come from an a3 auto!

thanks for the reply, got all the correct power supplys and earths double checked! definitly got no earth trigger from pin 4 to activate fuel relay! when i switch the ignition key i can hear a  few things clickin and buzzing, i know that dont mean much, but i reckon the ecu isnt demobilized correctly. looking at the Audi a3 diagrams pin 4   activates the main relay which also puts live power to injectors and coils etc..got it all cranking and stuff. this agu come from an a3 auto!

power to fuel pump?

all the right relays in place and known to be working?

well i wouldnt call it the main relay but yes pin 4 triggers the fuel pump relay which powers the injectors, lambda heater etc. put a switched live relay in or bridge the live to the fuel power pin to see if the car starts.

how have you wired up the relay? if you're using the factory relay slot on the fusebox you can fit a 17/18 relay to make the pump live with ignition. its not safe in the long run (if you have a crash) but it will help you diagnose the problem

I've done this,I bypassed the relay to get power to pump,injectors and coil packs etc but no joy! I still have no negative output on pin 4. I have constant +ve and -ve at the coil packs but no negative activation from the ecu to make them fire!    Basically im using this relay to power the above components as shown in the wiring diagrams (all individually fused)..All components have power but it seems the ecu isn't giving out earths , I reckon it's still immobilised ! The guy who did it is away for two weeks! Typical. Going to try and upload the diagrams I've bin working from… Thanks for your replays guys….

if it is still immobolised it would still fire for a couple of seconds

sounds to me like he has fried your ecu, or you have

even if it was immobilised it would still trigger the fuel pump even if it wont fire car. trouble is unless you tried the ecu before you sent it off no way to know if he killed it or if it was already dead. i have seen a few people with blown ecus they seem quite sensitive!

Not to mention expensive to replace and then have decoded again

Can you do de-immobilising Jonny as part of your service?

Not at the moment no, I'd need to buy chip readers and things and I dont really have the time! Toyotec should be able to do this soon if not already

Ok mate, Just hope mine works when i come to fire it up which hopefully should be within the next month or so.  

the ecu was fine i drove the car (audi a3) home! it ran perfect..ill wait for the guy to check the ecu again nxt week and go from there. cannot see the engine starting for a few seconds if imobilized tho!!!

yeah thats what they do, well mk3 golf engines do anyway and im pretty sure mk4 are the same

rubjonny said

yeah thats what they do, well mk3 golf engines do anyway and im pretty sure mk4 are the same

yep they do,

thanks for the help lads, see you ultimate dubs lol...