Information Bus: Testing and Inspection

Diagnosis

Diagnosis with the PIWIS tester is carried out via the CAN interface (diagnosis socket). Further key functions are available via the diagnosis interface:
- Read-out and erasure of fault memory
- Output of measurement and operating data (e.g. actual values)
- Actuator control
- Coding
- Calibration processes

Fault detection
The system incorporates a self-diagnosis facility which continuously monitors certain functions of the control unit or system components and records faults in a non-volatile fault memory (EEPROM).

Sensor default values
As on the previous model, in the event of a short-circuit or interruption of a sensor default values are employed to maintain operation of the a/c control system in emergency mode.