hi,

Looking for some pointers on this one please

Have a 2007 Audi A3 BKD engine. Has been fine until the other day - cranked, no start and the brake warning in instruments flashed up. After a bit of throttle it started and worked okay. Then the other day the fault re occurred but this time it was here to stay.



  • Cant communicate with the ECU but can with other modules
  • fans come on full speed almost straight away ( obviously engines cold )
  • fuse check out okay
  • swapped the relay "100" in engine compartment box for a known working unit - no change


I haven't got a wiring diagram but assume i either have a ECU power supply issue or the ECU is faulty

would appreciate some pointers please