# Lupo 1.8T AWM : start problem, 428 relay



## Laxen (Feb 25, 2012)

Hi,

I have a 2000 Lupo GTI with a 1.8T (AWM) engine conversion.



















One morning i suddenly had this in my ECU: 

*1 Fault Found:
17069 - ECM Power Relay Control Circuit (J271)
P0685 - 35-00 - Open Circuit
*
The problem seems to be that there is no ground coming to pin 85 to the ignition power relay (428) when the ignition is turned on. When I manually short this pin to ground I can hear the relay click and the engine also starts just fine.









_bigger picture_









_bigger picture_

Has anybody ideas where this (violet?) cable normally goes or where to find good 1.8T wiring diagrams, so I could start figuring out where the problem is.

Thanks in advance!

_:: edited some terrible spelling _


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## VRtits (Jun 23, 2006)

Any ideas on the source of this problem yet? I am swapping an ATC 1.8t into my mkII and ran into the same issue. That violet wire runs straight back to the 121 pin connector at the ECU, the ECU is supposed to provide it with the ground signal. I would assume it is supposed to provide it with the ground signal after key on, but I tested my brothers relay harness in his 20th and that relay seemed to stay powered even with the key out of the ignition......? But anyway the ecu is supposed to trigger that sensor. If you have got any ideas let me know!


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## VRtits (Jun 23, 2006)

The violet wire goes to t121/21.


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## WoLfBuRgJeTTa (Mar 4, 2006)

I am having the same exact issue, I found one other thread but no one ever responded to the guy. When I hook up my battery, the 428 relay clicks like crazy and the fuel pump turns on then on/off for a while and the car will crank but not start. This is the last step to finishing my swap, anyone got ideas to fix this?


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## WoLfBuRgJeTTa (Mar 4, 2006)

VRtits said:


> The violet wire goes to t121/21.


t121/21 is ECM Power supply relay from the ECM (J271)


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## VRtits (Jun 23, 2006)

I just bypassed the relay, connect switched and cranking 12v to purple/black and it should fire up


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## Laxen (Feb 25, 2012)

Sorry for responding this late.. ;(

Is was a wire that was cut, connected it and it all worked just fine.
Because of the engine swap the color of the cabel at the relay end wasn't the same as in the ECU end, so finding the right cable was quite a journey 

Now waiting for my GT28RS -installation to complete!


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## WoLfBuRgJeTTa (Mar 4, 2006)

Similar fix for mine, a sensor was unplugged because the harness was missing it, must have been cut off


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## MrSavvy (Mar 21, 2011)

I hate you. I want a Lupo. :wave:


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## Dashman182x (Dec 15, 2006)

Hey man that relay is in the black box above the brake boosts next to where the main engine harnssss run against the firewall




Laxen said:


> Hi,
> 
> I have a 2000 Lupo GTI with a 1.8T (AWM) engine conversion.
> 
> ...


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