For 1990-2009 cars

### Circuit Description

The steering wheel module deployment loop consists of an inflatable restraint steering wheel module, an inflatable restraint steering wheel module coil, the steering wheel module - high and steering wheel module - low circuits. A shorting bar is used in the inflatable restraint steering wheel module and the inflatable restraint steering wheel module coil connectors which will short together the steering wheel module - high and steering wheel module - low circuits when the connector is disconnected, this will help to prevent unwanted deployment of the inflator module during servicing. During a frontal crash of sufficient force the SDM will allow current to flow through the deployment loop in order to deploy the inflatable restraint steering wheel module. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a DTC will be stored.

### Conditions for Running the DTC

Ignition 1 Voltage is within the normal operating voltage range.

### Conditions for Setting the DTC

The SDM detects a low resistance condition in the steering wheel module deployment loop.

### Action Taken When the DTC Sets

The SDM commands the AIR BAG indicator ON.

### Conditions for Clearing the DTC

The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.

### Diagnostic Aids

Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction.

The following are possible causes of the malfunction:

• | A short between the steering wheel module - high and the steering wheel module - low circuits.

• | A malfunctioning inflatable restraint steering wheel module.

• | A malfunctioning inflatable restraint steering wheel module coil.

• | An internal SDM malfunction.

If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

### Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. Tests to see if the malfunction is caused by the inflatable restraint steering wheel module.

2. Tests to see if the malfunction is caused by the inflatable restraint steering wheel module coil.

3. Tests for a short between the Steering Wheel Module High and Steering Wheel Module Low circuits.

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: SIR Schematics
1 | Did you perform A Diagnostic System Check - SIR? | Go to Step 2 | Go to Diagnostic System Check - SIR
2 | Is DTC B0100 set as a current DTC? | Go to Step 3 | Go to Diagnostic Aids
3 |

1. Turn OFF the ignition.
2. Remove the steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement .
3. Inspect both the component and harness sides of the steering wheel module connector for damage or corrosion that may cause a short between the Steering Wheel Module - High and the Steering Wheel Module - Low circuits. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Does the connector exhibit any signs of damage or corrosion?

Go to Step 4

Go to Step 5

4 |

1. If the component side of the steering wheel module connector is damaged, the steering wheel module must be replaced. Refer to Inflatable Restraint Steering Wheel Module Replacement .
2. If the harness side of the steering wheel module connector is damaged, the steering wheel module coil must be replaced. Refer to Inflatable Restraint Steering Wheel Module Coil Replacement .

Did you complete the replacement?

Go to Step 12

--

5 |

1. Turn ON the ignition, with the engine OFF.
2. Use the scan tool in order to Clear the DTCs.
3. With the scan tool, request the SIR DTC display.

Does the scan tool indicate that DTC B0100 is current?

Go to Step 6

Go to Step 9

6 |

1. Disconnect the lower steering wheel module coil connector.
2. Use the scan tool in order to Clear the DTCs.
3. With the scan tool, request the SIR DTC display.

Does the scan tool indicate that DTC B0100 is current?

Go to Step 7

Go to Step 10

7 |

1. Turn OFF the ignition.
2. Disconnect the SDM connector.
3. Inspect the SDM connector for damage or corrosion that may cause a short between the Steering Wheel Module - High and the Steering Wheel Module - Low circuits. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 12

Go to Step 8

8 | Test for a short between the Steering Wheel Module - High and the Steering Wheel Module - Low circuits. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 12 | Go to Step 11
9 |

1. Turn OFF the ignition.
2. Replace the steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement .

Did you complete the replacement?

Go to Step 12

--

10 |

1. Turn OFF the ignition.
2. Replace the steering wheel module coil. Refer to Inflatable Restraint Steering Wheel Module Coil Replacement .

Did you complete the replacement?

Go to Step 12

--

11 | Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Did you complete the replacement? | Go to Step 12 | --
12 |

1. Reconnect all SIR components.
2. Verify that all components, connectors and CPAs are properly mounted.
3. Use the scan tool in order to Clear the DTCs.
4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK