Chaps, I found a d900 code on my dash diagnostics too. Tried a code reader and it came up with a P code wail about the diesel particulate filter. Discovered that the hugely expensive DPF itself was actually ok, but two rubber hoses connected to it were absolutely knackered and split. These hoses are in very close proximity to the exhaust so I wasn't comfy replacing them with boggo rubber pipe - got garage to source ford originals. Just had a vehicle fire on a movano & don't want a repeat!
Ford robbers charged well over £100 for these two lil bits of 'special' rubber pipe.... well, only to be expected
Did a battery reset (disconnect battery positive lead & touched to chassis then left for a few hours before reconnecting) and then cleared the P-codes using the code reader. Drove for a few hundred miles & great, DPF issue gone away no more DPF P code.
2 days later, limp home mode again. Looked at battery voltage realtime graph on code reader, 12.0V before start, 11.5V after start. rev it up, battery voltage v time graph flat line at 11.5V. Suspected alternator.
Gave to garage, yep, alternator. But, alternator on this car connected to ECU via 3-pin control connector. Alternator with this 'smart charge' technology is twice the price of standard alternator.
Alternator now replaced, did another battery reset & FCR reset.. car runs fine and charging batt ok. No faults being reported by FCR.
However, despite doing a 2 hour long battery reset including shorting the removed battery positive terminal to chassis, and despite doing a full fault code clear on the FCR, the D900 "non specific can communications error" on the dash diagnostic persists.
Would like the answer to one question if anyone has it.. how exactly, can you clear this D900 trouble code off the dash diagnostic, just to see if it comes back again?
I'm wondering if there's a persistent memory chip in the dash cluster or a little lithium battery or something. Where should I aim my lumphammer?