Supplemental Inflatable Restraint (SIR)

Code 51:

DERM Circuit Detail:

DESCRIPTION
The Diagnostic Energy Reserve Module (DERM) determines that the Arming Sensor is closed when system voltage or more is present at the "Sense Hi" input, and it determines that a Discriminating sensor in closed when it notes low voltage at the "Sense Low" input. There are some faults that may "look" like an accident to the DERM, and therefore record a code 51. History Code 51 therefore is not proof that the vehicle was in an accident.

TEST CONDITION
DERM energy reserve voltage OK.

FAILURE CONDITIONS
Current Code 51 will set if the DERM senses that both the Arming Sensor and at least one of the Discriminating sensors are closed simultaneously.

CONDITIONS TO CLEAR
Current code 51 can be cleared using a scan tool clear codes command. HISTORY CODE 51 WILL REMAIN IN THE DERM THEREAFTER.

ACTION TAKEN
DERM turns on the "INFLATABLE RESTRAINT" indicator until current Code 51 is cleared.

NOTES ON FAULT TREE
1. Incorrect diagnosis will occur if the SIR Diagnostic System Check is not performed

2. If a Code 51 is not current then this chart is not to be used.

3. If the Inflator Module has deployed then no further diagnosis is required. Otherwise, some further inquiry is required to fully diagnose the system.