For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptors

DTC B0012 01: Driver Airbag Squib Circuit (Stage 1) High Voltage
DTC B0012 02: Driver Airbag Squib Circuit (Stage 1) Low Voltage
DTC B0012 04: Driver Airbag Squib Circuit (Stage 1) Open
DTC B0012 0D: Driver Airbag Squib Circuit (Stage 1) High Resistance
DTC B0012 0E: Driver Airbag Squib Circuit (Stage 1) Low Resistance
DTC B0012 0F: Driver Airbag Squib Circuit (Stage 1) Shorted With Other Squib Circuit
DTC B0013 01: Driver Airbag Squib Circuit (Stage 2) High Voltage
DTC B0013 02: Driver Airbag Squib Circuit (Stage 2) Low Voltage
DTC B0013 04: Driver Airbag Squib Circuit (Stage 2) Open
DTC B0013 0D: Driver Airbag Squib Circuit (Stage 2) High Resistance
DTC B0013 0E: Driver Airbag Squib Circuit (Stage 2) Low Resistance
DTC B0013 0F: Driver Airbag Squib Circuit (Stage 2) Shorted With Other Squib Circuit

### Diagnostic Fault Information

Circuit | Short to Ground | Low Resistance | High Resistance | Open | Short to Voltage
--- | --- | --- | --- | --- | ---
Steering Wheel Module Stage 1 High Control | B0012 02 | B0012 0E | B0012 0D | B0012 04 | B0012 01
Steering Wheel Module Stage 1 Low Control | B0012 02 | B0012 0E | B0012 0D | B0012 04 | B0012 01
Steering Wheel Module Stage 2 High Control | B0013 02 | B0013 0E | B0013 0D | B0013 04 | B0013 01
Steering Wheel Module Stage 2 Low Control | B0013 02 | B0013 0E | B0013 0D | B0013 04 | B0013 01

### Circuit/System Description

During a frontal crash of sufficient force the inflatable restraint sensing and diagnostic module (SDM) will allow current to flow through the deployment loop in order to deploy the 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.

There are 2 shorting bars used within the steering wheel module connector which will short together both steering wheel module stage 1 high circuit and steering wheel module stage 1 low circuit and both steering wheel module stage 2 high circuit and steering wheel module stage 2 low circuit when the connector is disconnected. This will help to prevent unwanted deployment of the inflator module during servicing.

### Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

### Conditions for Setting the DTC

Any of the following conditions must exist for 1 second:

#### B0012 01 Stage 1 or B0013 01 Stage 2

The steering wheel module high and/or low circuit is shorted to voltage.

#### B0012 02 Stage 1 or B0013 02 Stage 2

The steering wheel module high and/or low circuit is shorted to ground.

#### B0012 04 Stage 1 or B0013 04 Stage 2

The steering wheel module high and/or low circuit is open.

#### B0012 0D Stage 1 or B0013 0D Stage 2

The steering wheel module deployment loop resistance is greater than 3.9 ohms.

#### B0012 0E Stage 1 or B0013 0E Stage 2

The steering wheel module deployment loop resistance is less than 2.1 ohms.

#### B0012 0F Stage 1 or B0013 0F Stage 2

An inflatable restraint module deployment loop high or low control circuit is shorted to another deployment loop high or low control circuit.

### Action Taken When the DTC Sets

• | The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.

• | The SDM will store a DTC, however if an event occurs system will still attempt deployments.

### Conditions for Clearing the DTC

• | The condition for setting the DTC no longer exists.

• | A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

### Reference Information

#### Schematic Reference

SIR Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

SIR System Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

• | Connector Repairs

#### Scan Tool Reference

Control Module References for scan tool information

#### Diagnostic Aids

Deployment loop DTCs, B0012 - B0045 with a symptom of 0F, are to be tested for a short between the one deployment loop high or low control circuits to the other deployment loop high or low control circuits. If the condition is found, make the appropriate repair.

### Circuit/System Testing

Important: Refer to SIR Service Precautions.

When removing connectors inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector:

• | Air bag module

• | SDM module

• | Air bag wiring harness connector

• | SDM wiring harness connector

Important: The connector and CPA may seat independent of each other. Both the connector and CPA should seat with an audible and/or tactile click. The CPA isolates the shorting-bars within the module connector allowing the deployment circuit to operate properly.

1. Verify that the steering wheel module connector and the connector position assurance (CPA) are engaged.

⇒ | If the above condition is not found, make the appropriate repair.

2. Ignition OFF, disconnect the appropriate steering wheel module harness connector.
3. Ignition ON, verify that the appropriate scan tool Driver Airbag Stage 1 or Stage 2 Squib Circuit Resistance parameter is infinite resistance while turning the steering wheel slowly in both directions.

⇒ | If less than the specified value, test for a short between the high control circuit, the low control circuit, and the steering wheel module coil and test the control and the steering wheel module coil. If the circuits test normal, replace the SDM.

4. Ignition OFF, at the appropriate steering wheel harness connector, connect a fused jumper wire between the high control circuit terminal 2 and the low control circuit terminal 1.
5. Ignition ON, verify that the appropriate scan tool Driver Airbag Stage 1 or Stage 2 Squib Circuit Resistance parameter is less than 2.1 ohms, while turning the steering wheel slowly in both directions.

⇒ | If greater than the specified range, test the appropriate high control circuit and low control circuit for an open/high resistance.

⇒ | If the circuits test normal, replace the SDM.

6. Ignition OFF, remove the fused jumper wire.
7. Disconnect the harness connector at the SDM.
8. Ignition ON, test for less than 1 volt between the appropriate high control circuit terminal 1 at the steering wheel module coil connector and ground.

⇒ | If greater than the specified range, test the high control circuit for a short to voltage.

9. Test for less than 1 volt between the appropriate low control circuit terminal 2 at the steering wheel module coil connector and ground.

⇒ | If greater than the specified range, test the low control circuit for a short to voltage.

10. Ignition OFF, test for infinite resistance between the appropriate high control circuit terminal 1 at the steering wheel module coil connector and ground.

⇒ | If less than the specified value, test the high control circuit for a short to ground.

11. Test for infinite resistance between the appropriate low control circuit terminal 2 at the steering wheel module coil connector and ground.

⇒ | If less than the specified value, test the low control circuit for a short to ground.

Important: The connector and CPA may seat independent of each other. Both the connector and CPA should seat with an audible and/or tactile click. The CPA isolates the shorting-bars within the module connector allowing the deployment circuit to operate properly.

12. Reconnect all the components and connectors. Verify that the steering wheel module connector and the connector position assurance (CPA) are engaged.
13. Ignition ON, verify that the appropriate scan tool Driver Airbag Stage 1 or Stage 2 Squib Circuit Resistance parameter is between 2.1-3.9 ohms, while turning the steering wheel slowly in both directions.

⇒ | If not within the specified value, replace the steering wheel module.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Steering Wheel Inflatable Restraint Module Replacement

• | SIR/SRS Wiring Repairs

• | Control Module References for SDM replacement, setup, and programming