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. One test the SDM performs is to monitor the driver side high circuit and driver side low circuit voltage difference. By monitoring voltage difference, the SDM is able to calculate the driver loop resistance. High resistance indicates an open somewhere in the driver deployment loop.

### DTC Test Conditions:

DTC B0022 can be set when the driver loop resistance is high. The following conditions must be met to set this DTC:

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

• | The driver deployment loop resistance is under 4.8 ohms or circuit 347 under 2 volts and loop resistance over 6 ohms.

• | Fault needs to only be present for less than half a second or five consecutive sample readings.

### Action Taken:

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

• | The air bag light will be turned on.

### Diagnostic Aids:

When attempting to diagnose an intermittent driver loop fault, use the scan tool to monitor current DTCs. Wiggle wires, turn steering wheel, and check connections while watching for current DTC to appear and/or disappear on Scan Tool.

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

An open in circuits 347 and 348 to the driver inflator module could cause this DTC.

Always perform the SIR Diagnostic System Check Procedure before using this chart

When measurements are requested in this chart use SA 91114NE digital multimeter with correct terminal adapter from SA 9206Z. When a check for proper connection is requested refer to Intermittent and Poor Connections in Wiring Systems. When a wire connector or terminal repair is requested, use the proper repair parts and refer to Wiring Repairs in Wiring Systems.

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. Disconnect driver yellow two way connector located at base of steering column.
3. Check for corroded or damaged harness terminals.

Are the terminals OK?

Go to Step 4

Go to Step 3

3 |

1. Refer to Wiring Repairs in Wiring Systems.
2. Replace terminal(s) with appropriate SIR lead kit.

Are the repairs complete?

Go to Step 13

--

4 |

1. Turn OFF the ignition.
2. Connect SA9409-Z SIR load tool to driver harness connector (yellow two way connector located at base of steering column).
3. Turn ON the ignition.

Is DTC B0022 current?

Go to Step 5

Go to Step 10

5 |

1. Turn OFF ignition.
2. Disconnect SDM9409-Z SIR load tool.
3. Disconnect SDM connector.
4. Measure resistance of circuit 347 from SDM connector to driver harness connector at base of steering column.

Does the digital multimeter display 1 ohm or less?

Go to Step 7

Go to Step 6

6 |

1. Turn OFF the ignition.
2. Repair open or cause of high resistance in circuit 347 from SDM to driver harness connector at base of steering column.

Are the repairs complete?

Go to Step 14

--

7 |

1. Turn OFF the ignition.
2. Disconnect SA9409-Z load tool.
3. Disconnect SDM connector.
4. Measure resistance of circuit 348 from SDM connector to driver harness connector at base of steering column.

Does the digital multimeter display 1 ohm or less?

Go to Step 9

Go to Step 8

8 |

1. Turn OFF the ignition.
2. Repair open or cause of high resistance in circuit 348 from SDM to driver harness connector at base of steering column.

Are the repairs complete?

Go to Step 14

--

9 |

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

Are the repairs complete?

Go to Step 14

--

10 |

1. Turn OFF the ignition.
2. Remove driver inflator module from steering wheel.
3. Disconnect the coil assembly harness from the inflator module.
4. Measure resistance of circuit 347 from driver harness connector at base of steering column to inflator connector on coil assembly.

Does the digital multimeter display 1 ohm or less?

Go to Step 11

Go to Step 12

11 |

1. Turn OFF the ignition.
2. Remove driver inflator module from steering wheel.
3. Disconnect the coil assembly harness from the inflator module.
4. Measure resistance of circuit 348 from driver harness connector at base of steering column to inflator connector on coil assembly.

Does the digital multimeter display 1 ohm or less?

Go to Step 13

Go to Step 12

12 |

1. Turn OFF the ignition.
2. Replace coil assembly.

Are the repairs complete?

Go to Step 14

--

13 |

1. Turn OFF the ignition.
2. Replace the driver inflator module.

Are the repairs complete?

Go to Step 14

--

14 |

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

Was the Diagnostic System Check performed after repair?

--

Go to Step 15

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