Audi Q7 2006 4lb. Turns over but won't start. Will run on easystart. ECU replacement as got wet by the rain, ECU files transferred from old ECU to new ECU, have power at pump relay, but no power to fuel pumps. Fuel pumps work when triggered with diagnostic scanner, also work when power applied directly, bridge pump relay the pumps work also.

Has power to pump relay. Have checked fuses, changed fuel pump relay, could it possibly be faulty fuel pump module? Pump module located underneath above the exhaust. From the pump relay to pump apart from fuel pump module does the connection run through anyother unit, that I have missed?

Edited September 4, 2025Sep 4 by Q7b4825
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Is it an imobiliser issue? Even on my old A6 the imobiliser is linked to the instrument cluster, ECU, high pressure fuel pump ECU. They all need to talk so it'll start. 

Hiya Steve. I'm glad for your reply, as I've been researching just this, would the immobilizer be the issue even if new ECU has direct clone of old ECU files?

I brought a signal test ring, to test immobilizer signal test, also I have obdeleven and icarsoft V3, have you used a diagnostic scanner to test immobilizer signal? If you have how did you go about this? Any advice would be much appreciated, I'm at about £800 so far with parts, programming etc.

Glynn