gearbox ecu will need a reasonable code reader.
also, need to fix throttle sensor first!
Apparently the car was working OK, no reported faults, and then (following an abrupt stop) the gearbox warning came on and the engine speed no longer responded to the pedal.
Is it likley that two completely separate systems would have failed at the same time? Or more likley that (say) the gearbox fault forces a degraded engine operation?
I'm with Mark's DTM Calib, to see if the throttle position is reported correctly by the Engine ECU. Unless you happen to know if the 'box ECU fault causes the Engine ECU to go into degraded mode by overriding the supply signals to the two position sensors (hardware solution that would override any software faults). In which case, the Engine ECU is correct in its report, but the cause is still not the actual sensor but the excitation for the sensor.
(Happy to go fully into the technology on this; I work with electronic controllers in the avionics industry. Just don't know the logic/ground rules for the automotive versions)
My main problem is that I don't have access to a code reader or diagnostic monitor for the ECUs, so can neither monitor the throttle position nor read the gearbox fault codes. So I'm guessing from the outside.
Unless I can swap in components from the Petrol V6 Auto (same year) to assist diagnosis.
Oh, yes, still waiting for Haynes Manual, too, so anything special to vehicle is outside my knowledge.