Intermmittent ECU supply failure.

Initially I thought that I had fixed this by replaceing the main relay in the fusebox next to the battery, but Fault appears to persist.

I am thinking that this is going to be either an ignition switch problem or a wiring one but I note from the Autodata wiring diagram that there is an MFU that seems responsible for operating the starter motor and powering up the ECU which is presumably switched by the ignition swich.

Unfortunatly Autodata does NOT provide any wiring diagrams showing how the MFU and Ign switch are related!

I dont suppose anybody has such a wiring diagram, or indeed, could tell me where this MFU actually is??

Cheers