For 1990-2009 cars
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Handling ESD Sensitive Parts Notice

### Circuit Description

When you first turn the ignition switch to the ON position, the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. Then the SDM performs the following continuous diagnostic tests on the deployment loops:

• | Deployment loop voltage out of range test

• | Deployment loop resistance measurement test

If the voltage out of range test detects a short to voltage condition, the resistance measurement test for that deployment loop will not be performed.

### Conditions for Setting the DTC

• | Ignition 1 voltage is within the normal operating voltage range.

• | Driver frontal deployment loop is not open.

• | Driver frontal deployment loop is not shorted to voltage.

• | Driver frontal deployment loop is not shorted to ground.

• | Driver frontal deployment loop resistance is less than 1.2 ohms for 500 milliseconds.

The driver frontal deployment loop consists of the following components:

• | Inflatable restraint steering wheel module.

• | Inflatable restraint steering wheel module coil.

• | Harness wiring of the driver frontal high circuit.

• | Harness wiring of the driver frontal low circuit.

• | Connector terminal contact.

This malfunction is detected during the deployment loop resistance measurement test.

### Action Taken When the DTC Sets

• | The SDM sets a DTC B1022.

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

### Conditions for Clearing the DTC

• | Current DTC

| The resistance of the driver frontal deployment loop is at least 1.2 ohms or more for 500 milliseconds.

• | History DTC

- | Issue a scan tool CLEAR CODES command.

- | Once 250 malfunction free ignition cycles have occurred.

### Diagnostic Aids

The following can cause an intermittent condition:

• | A short between the driver frontal high circuit and the driver frontal low circuit.

• | A malfunctioning shorting bar on the inflatable restraint steering wheel module yellow 2-way connector.

• | A malfunctioning shorting bar on the inflatable restraint steering wheel module coil side of the inflatable restraint steering wheel module yellow 2-way connector.

### Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

1. This step checks the inflatable restraint steering wheel module yellow 2-way connector.

2. This step determines if the inflatable restraint steering wheel module coil or the inflatable restraint steering wheel module is malfunctioning.

3. This step determines if there is a short between the driver frontal high circuit and the driver frontal low circuit or if there is a malfunctioning SDM.

#### DTC B1022 Driver Frontal Deployment Loop Resistance Low

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 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the inflatable restraint steering wheel module yellow 2-way connector.
3. Inspect the wiring harness side of the inflatable restraint steering wheel module yellow 2-way connector for corrosion or damaged terminals.

Are the inflatable restraint steering wheel module yellow 2-way connector and terminals free from damage and corrosion?

--

Go to Step 4

Go to Step 3

3 | Repair or replace the wiring harness side of the inflatable restraint steering wheel module yellow 2-way connector. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 12 | --
4 |

1. Reconnect the inflatable restraint steering wheel module yellow 2-way connector.
2. Make sure that the connector position assurance (CPA) is properly installed.
3. Turn the ignition switch to the ON position.
4. Use the scan tool to request the SIR DTC display.

Is DTC B1022 current?

--

Go to Step 5

Go to Diagnostic Aids

5 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the inflatable restraint IP module yellow 2-way connector and the inflatable restraint steering wheel module yellow 2-way connector.
3. Install the J 38715-A SIR Driver/Passenger Load Tool to the wiring harness side of the inflatable restraint IP module yellow 2-way connector and the inflatable restraint steering wheel module yellow 2-way connector. Use the J 38715-25 adaptor for inline connector the inflatable restraint steering wheel module yellow 2-way connector and the J 38715-15 adaptor for the inflatable restraint IP module yellow 2-way connector.
4. Turn the ignition switch to the ON position.
5. Use the scan tool to request the SIR DTC display.

Is DTC B1022 current?

--

Go to Step 9

Go to Step 6

6 |

1. Turn the ignition switch to the OFF position.
2. Remove the inflatable restraint steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement .
3. Disconnect the J 38715-A from the inflatable restraint steering wheel module yellow 2-way connector.
4. Connect the inflatable restraint steering wheel module yellow 2-way connector back together.
5. Connect the J 38715-A to the upper inflatable restraint steering wheel module coil connector on the steering column. Use the J 38715-30 adaptor for the upper coil connector.
6. Turn the ignition switch to the ON position.
7. Use the scan tool to request the SIR DTC display.

Is DTC B1022 current?

--

Go to Step 8

Go to Step 7

7 |

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

Is the repair complete?

--

Go to Step 12

--

8 |

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

Is the repair complete?

--

Go to Step 12

--

9 |

1. Turn the ignition switch to the OFF position.
2. Disconnect the inflatable restraint sensing and diagnostic module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .
3. Disconnect the J 38715-A .
4. Use the J 39200 Digital Multimeter (DMM) to measure the resistance between terminal A6 and terminal A7 of the SDM wiring harness connector.

Is the measured resistance less than the specified value?

OL

Go to Step 10

Go to Step 11

10 | Locate and repair a short between the driver frontal high circuit and the driver frontal low circuit. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 12 | --
11 | Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Is the repair complete? | -- | Go to Step 12 | --
12 |

1. Reconnect all SIR components.
2. Make sure that all components and connectors are properly mounted.
3. Turn the ignition switch to the ON position.
4. Use the scan tool to clear all current and history SIR DTCs.

Have all current and history SIR DTCs been cleared?

--

Go to SIR Diagnostic System Check

--