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). The principle behind VIDA information presentation is the same as for other on-board diagnostic (OBD) systems.

Fault indication
The driver is warned via the combined instrument panel if any fault occurs in the SRS system.
A VIDA station must be connected to the car data link connector (DLC) in order for a fault source to be identified.

Diagnostic trouble codes (DTCs)
The control module will store a diagnostic trouble code (DTC) if it detects a fault. The control module can store up to 10 diagnostic trouble codes (DTCs).
If a fault disappears for any reason after the diagnostic trouble code (DTC) has been permanently stored in the control module, information about the fault remains in the control module.

Reading and erasing diagnostic trouble codes (DTCs)
Stored diagnostic trouble codes (DTCs) can be read off and erased using this function.
After the diagnostic trouble code (DTC) is stored the function can also read off if the fault is still present (permanent fault), or if the fault has disappeared for any reason (intermittent fault).
Diagnostic trouble codes (DTCs) can only be erased when all diagnostic trouble codes (DTCs) have been read at least once.

Data read-out
Data can be read off with this function.

SRS warning lamp
Read off the status of the SRS indicator lamp, lamp lit or lamp unlit.

Seat belt, driver and passenger
Reads off whether the driver or passenger is secured or not.

Seat belt buckle
Reads off whether the seat belt buckle functions or not.

Side impact sensor
Reads off the status of the different side impact sensors, for example no signal obtained.

Reading off the control module identification
VIDA identifies the control modules by reading off a number of codes from the control module memory.
The codes contain information about the control module's:
- hardware P/N (control modules without software)
- hardware serial number (control modules without software)
- side impact sensor serial number
- software P/N
- P/N diagnostic software.