i assume its there so ecu doesnt loose its settings and such, trace that green/red and red/black back to where it comes from it must have shorted to ground somewhere what it is, on the original loom the green/red wire comes from a fusebox perm live feed. This then splits to give the ecu perm live on pin 62 and the ecu relay perm live via the red/black wire on both the switched input and power input. This is because on these the ecu/coil power relay is earth triggered, not ignition triggered. So instead of ecu relay beign switched by ignition as on some other cars the ecu gets an ignition live to pin 3 and then it earths the ecu relay to switch on the coilpacks and also an additional power feed to ecu pin 121
I think I must have damaged the burnt wire when I hastily traced the black ecu power On a better note before this happened I had the car running for a few seconds I need to label the original loom connectors and make sure I put them back correctly as my fuel pump runs constantly when ignition is on Sent from my C6903 using Tapatalk
It stopped after a few seconds before I took out the 8v, I must have connected some wires wrong as my indicators won't flash either, I did take pics of where everything went but my phone died and deleted them all :-( Sent from my C6903 using Tapatalk
look at d/13, you should have a purple/white wire to the ecu pin 65. this pin should not be earthed! look at E/14 as well, there is a spade hanging off it make sure there is nothing ignition live to this, if in doubt unplug. this is where you plug your fuel pump power wires in for the engien loom such as injectors, lambda heater etc
I have the purple/white joined to d13. There are not too many damaged other wires, that purple/white was one that ran next to the fried one so I replaced it, E14 when I checked it yesterday before burnout seemed to be earthed.. No point me looking at it until the damaged wires are fixed, most are now done but still a few to sort and then try to find a suitable replacement wire for the burnt one More tomorrow :-) Sent from my C6903 using Tapatalk
I seem to be banging my head against the wall re wired the burnt out wire, it was the permanent live that goes to ECU power and joins the thick ECU wire Now every time i try to connect it it tries to do the same again I have checked and the black/purple single pin wire on the engine wiring loom goes to earth, i know it should not but it does so every time i try to add power the thinner wire get warm I disconnected the ECU plug and tested the wires Also disconnected the T14 I have removed the plugs for the injectors and checked it, still earth, removed the coilpacks wires, still earth that is as far as i went before i came indoors to brood like a small child It really is not FAIR !! What could be causing this to go to earth ? i have never opened the engine loom so i cant have caused any issues What else does the black/purple power on the engine loom ?, i have had a look at the wiring diag and it seems to just go to injectors and coil packs Strange that this power goes to earth... very strange At least i know its not the main wiring loom causing the issue, just the engine loom.. how many times have i stripped back and checked my own work today before i had an epiphany and checked the engine loom ! I'll have another look tomorrow
If you have disconnected all components on the loom. It must be earthed to chassis somewhere. Or connected to the wrong place.
the black/purple from ecu relay should go to 2 places, the coil packs and ecu pin 121 via the 2 pin plug on the small plug ecu loom. disconnect the 2 pin plug and try again, if it still goes to earth trace it back to where it comes from, carefully checking for splits in the insulation. Double check where you tapped it into on the fusebox too if you deleted the mk4 ecu relay and are using the mk2 socket, it should go to G1/10. if it isnt earthed once the small loom is unplugged, then the fault must be in the ecu loom somewhere. its common for the coilpack wiring to crack up so i would start there
With the engine loom completely disconnected from the ECU, T14 and single black/purple 2 pin I still get earth signal on that Black/purple I'll have a look tonight to see if any insulation is damaged and earthing out, I got fed up Saturday and left it alone Sunday Sent from my C6903 using Tapatalk
I attacked the engine wiring tonight and stripped it back from the big purple/black plug This is what I found One of the coilpack wires was mangled and touching an earth, explaining why my power went straight to earth Also I found lots of age related cracking and even some insulation that seemed to have disappeared! (pic above) After a couple of hours of replacing damaged wires the coilpack wiring now looks like this Having all this apart gives me a chance to tidy up and delete any wires I don't need like SAI etc I will post up more progress tomorrow Sent from my C6903 using Tapatalk
I need 2 more coilpack plugs as someone snapped off the holding clips in the past Anyone have a spare pair sitting about? Sent from my C6903 using Tapatalk
Should I be getting any power from e14? E14 comes out of the plug and splits to a spade, what wire from the original engine bay loom did this connect to? Or did it not connect to anything? I have wired my new e14 connections from the engine to a wire from the old loom and into the spade for e14, I have a feeling they should ONLY be connected to e14 not another wire too, I'll look at which wire I connected them to tonight, but I think it's this red/white I think these browns are earth and the yellow connector one goes to another yellow spade under the dash Sent from my Z1 using Tapatalk
e/14 should be live when the fuel pump relay is energised, on the gti you have 2 wires to this pin one does fuel pump, the other is a male spade for wiring to the engine electrics such as wur, aav, lambda heater etc depending on the engine. the brown/red with yellow spade is crankign live, not needed for mk4 ecu. brown wires 9 times out of 10 are earths, plug em to the claw above the fusebox. there is a brown wire hanging out the engien loom white plug, this needs to go to the big white earth jumper block that is on the thick brown coming in with the lighting loom.
Should that red/white be connected to e14? I have my E14 wires from mk4 loom sliced into this wire then plugged into e14 spare spade Sent from my C6903 using Tapatalk
You'll never believe it but... It bloody well runs!! I am over the moon, ok the wiring is all over the engine bay as I dared not wrap it until I was sure all was working and not about to go up in smoke again And the exhaust and boost pipes are off and there is a list as long as my arm of jobs still to do but I am as happy as a dog with 2 d1cks!! Huge thanks needs to go out to all that helped me get this far Especially wiring genius Rubjonny who has made the largest contribution of all Many thanks I'm sure I'll be asking more questions but for now I'll tape the loom and install it properly instead of thru the servo hole. Then get the servo back in the car Those are tomorrows jobs
Today was spent removing the loom and taping it all up, I routed the engine loom nicely and re did some of the vw loom covering The main loom is also back in the car, just needs connecting up, I got dragged to a family BBQ so had to finish early More tomorrow (unless I change the cam belt on Paul's ABF ) Sent from my iPad using Tapatalk
