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Diagnostic Functions






Diagnostic functions

General
The control module has a built-in diagnostic system, Volvo Diagnostic, which continuously monitors internal functions as well as input and output signals.

Diagnostic trouble codes (DTCs)
If the control module detects a fault, a diagnostic trouble code is generated. The control module can store up to 10 trouble codes. A fault that is detected during the most recent operating cycle is defined as permanent. Other faults that are detected are defined as intermittent.

Reading and erasing diagnostic trouble codes (DTCs)
Stored diagnostic trouble codes (DTCs) can be read off and erased using this function.
Diagnostic trouble codes (DTCs) can only be erased once all the diagnostic trouble codes (DTCs) have been read off at least once.

Reading off the control module identification
The control module can be identified by means of reading off a number of codes.
The codes contain information about the control module:
- hardware P/N (control module without software)
- hardware serial number (control module without software)
- software P/N
- diagnostic software P/N