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 Frontal Deployment Loop Stage 1 Short to Battery
DTC B0012 02: Driver Frontal Deployment Loop Stage 1 Short to Ground
DTC B0012 04: Driver Frontal Deployment Loop Stage 1 Open Circuit
DTC B0012 0D: Driver Frontal Deployment Loop Stage 1 Resistance Above Threshold
DTC B0012 0E: Driver Frontal Deployment Loop Stage 1 Resistance Below Threshold
DTC B0013 01: Driver Frontal Deployment Loop Stage 2 Short to Battery
DTC B0013 02: Driver Frontal Deployment Loop Stage 2 Short to Ground
DTC B0013 04: Driver Frontal Deployment Loop Stage 2 Open Circuit
DTC B0013 0D: Driver Frontal Deployment Loop Stage 2 Resistance Above Threshold
DTC B0013 0E: Driver Frontal Deployment Loop Stage 2 Resistance Below Threshold

### Diagnostic Fault Information

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

### Circuit/System Description

If a malfunction is detected, a DTC will be stored in non-volatile memory. 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 each 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

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

The steering wheel module high and/or low circuit is shorted to voltage for 120 milliseconds.

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

The steering wheel module high and/or low circuit is shorted to ground for 120 milliseconds.

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

The steering wheel module high and/or low circuit is open for 120 milliseconds.

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

The steering wheel module deployment loop resistance is greater than 5.1 ohms for 120 milliseconds.

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

The steering wheel module deployment loop resistance is less than 1.3 ohms for 120 milliseconds.

### 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 the 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.

### Diagnostic Aids

This DTC usually indicates a poor connection or a wiring malfunction between the SDM and the deployment loop.

### 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

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

#### Special Tools

J 38715-A SIR Driver/Passenger Load Tool

### Circuit/System Testing

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

• | Pretensioner

• | Air bag module

• | SDM module

• | Air bag wiring harness connector

• | SDM wiring harness connector

Important: The connector and connector position assurance (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 connector allowing the deployment circuit to operate properly.

1. Verify that the steering wheel module connector and the CPA are engaged.

⇒ | If the above condition is found, make the appropriate repair.

2. Ignition OFF, disconnect the appropriate harness connector at the steering wheel module.
3. With the appropriate load tool adaptor, connect special tool J 38715-A in place of the steering wheel module.
4. Ignition ON, verify DTC is set as current.

⇒ | If the DTC is not set or is set as history, cycle ignition OFF, disconnect the adapter and J 38715-A , reconnect the harness connector at the steering wheel inflator module, and cycle the ignition ON. If the DTC resets after reconnecting the module, replace the steering wheel inflator module.

5. Ignition OFF, disconnect special tool J 38715-A .
6. Disconnect the X3 harness connector at the steering wheel module coil.
7. With the appropriate load tool adaptor, connect special tool J 38715-A in place of the steering wheel module.
8. Ignition ON, verify DTC is set as current.

⇒ | If DTC is not set or is set as history, replace the steering wheel module coil.

9. Ignition OFF, disconnect special tool J 38715-A and the adaptor.
10. Disconnect the harness connector at the SDM.
11. Ignition ON, test for less than 1 volt between the appropriate high circuit listed below and ground:

• | Steering wheel module coil connector Stage 1 terminal 2 X3

• | Steering wheel module coil connector Stage 2 terminal 4 X3

⇒ | If not within the specified range, test the circuit for a short to voltage.

12. Test for less than 1 volt between the appropriate low circuit listed below and ground:

• | Steering wheel module coil connector Stage 1 terminal 1 X3

• | Steering wheel module coil connector Stage 2 terminal 3 X3

⇒ | If not within the specified range, test the circuit for a short to voltage.

13. Ignition OFF, test for infinite resistance between the appropriate high circuit listed below and ground:

• | Steering wheel module coil connector Stage 1 terminal 2 X3

• | Steering wheel module coil connector Stage 2 terminal 4 X3

⇒ | If not the specified value, test the circuit for a short to ground.

14. Test for infinite resistance between the appropriate low circuit listed below and ground:

• | Steering wheel module coil connector Stage 1 terminal 1 X3

• | Steering wheel module coil connector Stage 2 terminal 3 X3

⇒ | If not the specified value, test the circuit for a short to ground.

15. Test for less than 1 ohm between the high control circuit terminals listed below:

• | Steering wheel module coil connector Stage 1 terminal 2 X3 and SDM terminal 14

• | Steering wheel module coil connector Stage 2 terminal 4 X3 and SDM terminal 17

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

16. Test for less than 1 ohm between the low control circuit terminals listed below:

• | Steering wheel module coil connector Stage 1 terminal 1 X3 and SDM terminal 15

• | Steering wheel module coil connector Stage 2 terminal 3 X3 and SDM terminal 16

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

17. If all circuits test normal, replace the SDM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Inflatable Restraint Steering Wheel Module Coil Replacement

• | Inflatable Restraint Steering Wheel Module Replacement

• | SIR/SRS Wiring Repairs

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