SRS Diagnostic Functions

SRS diagnostic functions

Diagnostic trouble codes (DTCs)
If the control module detects a fault it stores a diagnostic trouble code (DTC) and the SRS indicator lamp light lights.
The only time the warning lamp does not light is when the cable between the control module and combined instrument panel is short-circuited to ground or if the bulb is blown. When the ignition is switched on the lamp should light for approximately 3 seconds and then go out if no diagnostic trouble code (DTC) is stored.
The control module can store up to 10 diagnostic trouble codes (DTCs).
If for some reason a fault disappears after the diagnostic trouble code (DTC) has been permanently stored in the control module, information about the fault is stored in the control module. Each diagnostic trouble code (DTC) also has a counter which displays if the fault is active or passive. If the counter value is 0 the control module interprets the fault as being intermittent (passive in other words). If the counter value is greater than 0 the control module interprets the fault as permanent (active).
The counter uses VIDA during fault-tracing which enables easy checking of the fault status; whether it disappears or remains. The diagnostic trouble code (DTC) status row is updated continuously and switches to intermittent fault if the fault is no longer present and permanent if the fault remains.

Reading and erasing diagnostic trouble codes (DTCs)
Diagnostic trouble codes (DTCs) can only be erased when all stored diagnostic trouble codes (DTCs) have been read off at least once. The diagnostic trouble code (DTC) status must also be intermittent (the fault is no longer active).