ABS rotational speed – Incorrect or unreliable data
Check whether fault codes have been generated for the BMS brake system, also check the rear axle gear configuration and wheel radius configuration in gearbox control unit. If fault code 65415 is also present, then check fault codes in the AWD control unit.
What you'll see
No driver-visible symptom recorded.
System reaction
This rotational speed is used for comparison purposes to ensure that the automatic gearbox and TCO rotational speed sensors are supplying the correct information. If these rotational speed signals are correct, the system is not affected. Together with a permanent fault on the automatic gearbox engine speed sensor, the system goes into "Locked gear" mode.
Diagnostic depth
The fault code is generated if the sensor value deviates too much from the rotational speed signals from the engine, main shaft, layshaft and TCO.
The control unit obtains no or incorrect rotational speed signals from BMS, alternatively incorrect configuration for gear ratio of the central gear or wheel radius. If fault code 65415 is also present the fault is probably in the AWD control unit.