I'm chasing an "RHF air gap too large" fault, but working on the LH sensor because nano shows that that is the wheel that starts moving later than the others. To be sure that I knew which wheel nano was reporting for sure, I struck on the idea of disconnecting the LH sensor to prove that it was that wheel triggering the fault. Unfortunately i just got the error "e2" straight after. I reconnected the sensor, but now it doesn't respond at all (well, not sure it was responding before tbh), reports e2 or occasionally "e1"...and the faults message is back to RHF air gap too large

Any clues?

The ABS system is a bit weird. You have to exit and reboot the Nano before it will connect a second time. That might be what you need to do between each step.

true - worth a go : o)