Diagnostic Functions

Diagnostic functions

General




The on-board diagnostic (OBD) system for the supplemental restraint system module (SRS) continually diagnoses the function of supplemental restraint system components and stores any diagnostic trouble codes (DTCs). The diagnostic trouble codes (DTCs) can then be read off. Information is presented in the same way as with other diagnostic systems.

Fault indication
If a fault occurs in the SRS system the driver is warned in various ways via the combined instrument panel:
- the SRS indicator lamp lights up and text appears in the display
- the general warning lamp lights and text appears in the display
- information light and text in display (2008-)
A VIDA station must be connected to the data link connector (DLC) in order to identify the source of the fault.

Diagnostic trouble codes (DTCs)
A diagnostic trouble code (DTC) is stored if the control module detects a fault.
Should a fault disappear for any reason after being stored in the control module as a diagnostic trouble code, information on the fault remains stored in the control module. If a fault is no longer permanent, the diagnostic trouble code remains as intermittent.

Reading and erasing diagnostic trouble codes (DTCs)
Stored diagnostic trouble codes (DTCs) can be read off and erased using this function.
This function can also be used to read off whether the fault is still present (permanent) or whether it has now ceased (intermittent) after the diagnostic trouble code (DTC) has been stored.
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 parameters
Data can be read off from the supplemental restraint system module (SRS) using this function.
Vehicle type
Read out which type of vehicle is programmed in the supplemental restraint system module (SRS).
Steering
Read out which type of steering is programmed in the supplemental restraint system module (SRS) - left-hand or right-hand drive.
Passenger airbag
Read out whether the supplemental restraint system module (SRS) is programmed for a front passenger airbag.
Also read out the status of the airbag.
Front passenger airbag switch
Reads out whether the supplemental restraint system module (SRS) is programmed to be equipped with a switch. Also reads out the status of the switch.
Occupant weight sensor (OWS)
Read out whether the supplemental restraint system module (SRS) is programmed for an occupant weight sensor (OWS).
Front seat belt buckle
Reads off the status of the driver and passenger seatbelt buckles.
Rear seat belt detection
Reads out whether the supplemental restraint system module (SRS) is programmed for seat belt detection, i.e. rear belt buckles containing a Hall sensor.
Rear belt buckles
If the vehicle is equipped with rear seat belt detection, the status of the belt buckles can be read out.
Battery voltage
Reads off the level of the power supply to the control module.

Reading off control module identification
The control module can be identified by reading off information from the control module's memory. The codes contain information about the control module's:
- hardware P/N (control module without software)
- hardware serial number (control module without software)
- software P/N
- software number, diagnostics.
The following information can also be read off from the control module memory:
- serial number, side impact sensor
- serial number, occupant weight sensor (OWS) (USA/CAN only).

Occupant weight sensor (OWS) calibration (USA/CAN only)
The occupant weight sensor (OWS) can be calibrated using this function.