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Diagnostic Functions






Diagnostic functions





General
The on-board diagnostic (OBD) system for the SRS continually diagnoses the function of SRS system components and stores any diagnostic trouble codes (DTCs). However, the diagnostics for the two front seat belt buckles are carried out by the central electronic module (CEM) which also stores any diagnostic trouble codes (DTC) for them. If a fault is registered for longer than 5 minutes, the central electronic module (CEM) transmits the diagnostic trouble code (DTC) to the SRS control module. The SRS module then stores diagnostic trouble code(s) (DTC) for the front seat belt buckles. The diagnostic trouble codes (DTCs) can then be read off via VIDA. The principle behind VIDA information presentation is the same as for other on-board diagnostic (OBD) systems.

Fault indication
The driver is warned in a number of ways via the combined instrument panel if any fault occurs in the SRS system:
- SRS warning lamp and text in the display
- The general warning lamp lights up in red and there is text in the display
- The orange general warning lamp and text in the display.
A VIDA station must be connected to the car data link connector (DLC) in order for a fault source to be identified.

Diagnostic services
The following diagnostic services are available for the SRS system:
- Read off diagnostic trouble codes (DTCs) (maximum of 5 codes)
- Erase diagnostic trouble codes (DTCs) (all DTCs except those stemming from internal faults in the SRS control module can be erased)
- The identity of the SRS control module. The software that is installed can be read off via the VIDA station.