Self-diagnosis

Self-diagnosis

Through suitable control logics of the sensors and adjustment with "self-learning" of the actuators, the electronic control unit is capable of recording and storing a series of faults and failures which may occur in the system.

In the event of such faults the control unit still continues to manage the system replacing any abnormal values with suitable "recovery" values which ensure minimal operation, even if not perfect, of the system.

The errors stored can be read by the ALFA ROMEO TESTER, and there are two types:

• "occasional" errors, which are reset with the ignition key at STOP
• "permanent" errors: if an error occurs more than 5 times in a determinate time it is considered as permanent and memorised in the control unit; these errors are NOT reset with the key at STOP, but only after a specific outside command (Tester).

A preliminary system check is possible through TEST A.

FAULT-FINDING TABLE

NOTE: The fault-finding table for the air conditioner has been subdivided into three sections to simplify interpretation, which contain the three functions shown separately also in the wiring diagrams:

• Climate control fan, air temperature and recirculation control (see SELF-DIAGNOSIS)
• Compressor control
• Engine fan control (see Sect. 32A) (B)

Compressor control