Originally Posted by
oldford
DTC codes D900 and E510 are exactly the same as U1900 and U2510.
Some of the can-bus seams to be working still. Otherwise the AA couldn't have read the 2 U codes.
So, it's probably not an ecu hanging up the bus, but a wiring problem in the can-bus somewhere between the instrument panel and the engine ecu and transmission ecu.
It's not between the instrument panel and the diagnostic connector. It is however also between the diagnostic connector and the engine and transmission ecu's.
Thanks oldford, I think the AA guy said he was able to get comms to the dash not the PCM. It took him a while to get codes out. I don't know too much about focus wiring (yet). I assume here is more than one canbus and maybe more than one on the OBDII port? I know some cars have K line along with canbus on the OBDII port.
I'm going to check the canbus impedance and take a look at it with a scope.
I'll pop the instrument cluster and check the connector soldering too.