For 1990-2009 cars

### Circuit Description

The inflatable restraint Sensing and Diagnostic Module (SDM) contains a sensing device that converts vehicle velocity changes to an electrical signal. The SDM processes the generated electrical signal and compares it 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 the signals stored in memory. When two of the generated signals exceed the stored values, the SDM will cause current to flow through the indicator modules, deploying the air bags and causing DTC B1051 to be set.

### Conditions for Setting the DTC

The SDM detects a frontal crash, up to 30 degrees off the centerline on the vehicle, of sufficient force to warrant deployment of the air bags.

### Action Taken When the DTC Sets

• | The SDM detects a diagnostic trouble code.

• | The SDM turns ON the AIR BAG warning lamp.

• | The SDM records crash data.

### Conditions for Clearing the DTC

DTC B1051 is a latched code. You cannot clear a latched code. Replace the SDM after following the instructions in the diagnostic table.

### Test Description

Numbers below refer to step numbers on the diagnostic table:

1. If the inflator module has not deployed, DTC B1051 may be set falsely.

2. If DTC B1051 has set with no signs of frontal impact, the diagnostic trouble code has set falsely.

#### DTC B1051 Deployment Commanded

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Was the SIR Diagnostic System Check performed? | -- | Go to Step 2 | Go to SIR Diagnostic System Check
2 | Turn the ignition switch to the LOCK position. Has the inflator module deployed? | -- | Go to Step 5 | Go to Step 3
3 | Inspect the front of the vehicle and the undercarriage for signs of impact. Are signs of impact visible? | -- | Go to Step 5 | Go to Step 4
4 | Replace the inflatable restraint Sensing and Diagnostic Module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Have you replaced the SDM? | -- | Go to Step 6 | --
5 | Replace components and perform inspections. Refer to Repairs and Inspections Required After a Collision . Have you completed the appropriate repairs and inspections? | -- | Go to Step 6 | --
6 | Reconnect and mount all of the SIR system components. Have you reconnected and properly mounted all of the SIR components? | -- | Go to SIR Diagnostic System Check | --