Software Monitoring, Implausible Calculation Of Engine Rpm Control Intervention

P189A

Diagnosis information - PDK

Software monitoring, implausible calculation of engine rpm control intervention

Diagnostic conditions
The control unit initially tests internal function sequences when the ignition is switched on (terminal 15). If they are OK, all diagnosable outputs are then tested and any faults are stored.

- Ignition on

Possible fault causes
- PDK control unit faulty

Fault setting conditions
- Fault in calculation path for engine speed control

Fault effects
- Transmission limp-home indication in instrument cluster control unit
- Message counter stopped