Circuit Description
The inflatable restraint sensing and diagnostic module (SDM) contains sensing device (accelerometer) that converts vehicle velocity changes to an electrical signal. The SDM compares this electrical signal to a value stored in memory. When the generated signal exceeds the stored value, the SDM performs additional signal processing and compares the generated signals to values stored in memory. When two of the generated signals exceed the stored values, the SDM will cause current to flow through the inflator modules, deploying the air bags and causing DTC B0051 to set.
Conditions for Setting the DTC
The SDM detects a frontal crash, up to 30 degrees off the centerline of the vehicle, of sufficient force to warrant deployment of the frontal air bags.
Action Taken When the DTC Sets
| • | The SDM sets a DTC B0051. |
| • | The SDM commands ON the AIR BAG warning lamp via Class 2 serial data. |
| • | The SDM records crash data. |
Conditions for Clearing the DTC
DTC B0051 is a latched code. You cannot clear a latched code. The SDM must be replaced.
Test Description
The numbers below refer to the step numbers on the diagnostic table:
-
If the inflator module(s) has not deployed, DTC B0051 may have set falsely.
-
If DTC B0051 has set with no signs of frontal impact, the DTC may have set falsely.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the SIR Diagnostic System Check performed? | -- | ||
Turn the ignition switch to the OFF position. Has the inflator module(s) deployed? | -- | |||
Inspect the front of the vehicle and the undercarriage for signs of impact. Are there signs of impact? | -- | |||
4 | Replace the inflatable restraint sensing and diagnostic module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Is the repair complete? | -- | -- | |
5 |
Have the appropriate inspections and repairs been made? | -- | -- | |
6 |
Have all the SIR components been reconnected and properly mounted? | -- | -- |
