I've just (almost) completed an ME7.5 conversion on my B5 A4.

I've had a base map written, based on 018CB code from a TT225.

I've got two ME7.5 ECU's handy, an 032HL from a Skoda Octavia 1.8T Automatic, and a 032HN from a Golf 1.8T.

I grabbed one at random, and flashed the 018CB code on, and tried to start the car last night.

VCDS connects to the ECU, it reports some "missing message" codes and a code for the unplugged cam sensor, but otherwise seems happy, measuring blocks shows the engine cranking, and can see the throttle pedal input etc, and while cranking injector duty clocks up to 4ms, but the engine doesnt start. Just cranks endlessly.

It was getting late, and i didnt have much time to check things such as the power supplies to the coils and injectors, but given no fault codes were present i'm assuming they were good. I'll check properly when i get a chance, tonight perhaps. I'm about 90% sure i could here the fuel pump running while cranking, and it was definitely priming the pump when switching the ignition on.

Anyway while puzzling over it that evening i started to wonder about the crossflashed rom. It turned out the ECU i'd flashed was the Skoda one. The PCB hardware revision on the Skoda ECU was 2.3KA. The revision on the other ECU is 3.2WK, which i believe is the same as the BAM ECU my code comes from.

So is this possibly just an incompatibility between ROM and ECU? Or is it more likely i've missed a power connection or something? I'm going to try flashing the other ECU tonight and see if that sorts it, but just looking for some input in the mean time to see if i'm barking up the wrong tree or what.

they hl ecu would need the 018h file to work and as you found the 032hn works well with the 018cb