For 1990-2009 cars

### Circuit Description:

When the ignition switch is turned ON and during vehicle operation, the SDM performs tests to detect system faults. While the SDM is performing tests to detect system faults, tests are also performed on internal components of the SDM. When an internal SDM fault is detected this DTC is set.

### DTC Test Conditions:

DTC B1000 can be set when the SDM malfunctions. The following conditions must be met to set this DTC:

• | Ignition voltage is present at the SDM and continuous.

• | The SDM has detected an internal fault or an air bag deployment has been commanded.

• | Fault needs to only be present for less than half a second.

### Action Taken:

• | When this fault is detected a current DTC will be set.

• | The air bag light will be turned ON.

### Diagnostic Aids:

Always start diagnosis of SIR DTCs with an inspection of vehicle including its wiring and SIR components for visible damage.

Always replace SDMs with DTCB1000 set, only after all collision repairs have been completed.

Perform SIR Diagnostic System Check before proceeding with this chart.

Caution: Be careful when you handle a sensing and diagnostic module (SDM). Do not strike or jolt the SDM. Before applying power to the SDM:

• | Remove any dirt, grease, etc. From the mounting surface.

• | Position the SDM horizontally on the mounting surface.

• | Tighten all of the SDM fasteners and SDM bracket fasteners to the specified torque value.

Failure to follow the correct procedures could cause air bag deployment, personal injury, or unnecessary SIR system repairs.

Step | Action | Yes | No
1 | Did you perform the Diagnostic System Check - SIR? | Go to Step 2 | Go to SIR Diagnostic System Check
2 |

1. Turn OFF the ignition switch.
2. Inspect the vehicle for deployed air bags.

Have the air bags been deployed?

Go to Step 6

Go to Step 3

3 | Inspect front of vehicle and undercarriage for signs of impact. Are there signs of impact? | Go to Step 4 | Go to Step 5
4 |

1. Turn OFF the ignition.
2. Replace all damaged components.

Are the repairs complete?

Go to Step 5

--

5 |

1. Turn OFF ignition.
2. Replace the SDM.

Are the repairs complete?

Go to Step 7

--

6 |

1. Refer to Repair and Inspections Required After an Accident.
2. Replace the SDM.

Are the repairs complete?

Go to Step 7

--

7 |

1. Reconnect all components.
2. Clear all DTCs.

Was the Diagnostic System Check performed after repair?

--

Go to Step 8

8 | Perform the Diagnostic System Check. | -- | --