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 BatteryDTC 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 | B0012 02 | B0012 0D | B0012 04 | B0012 01 | B0012 0E |
Steering Wheel Module Stage 1 Low | B0012 02 | B0012 0D | B0012 04 | B0012 01 | B0012 0E |
Steering Wheel Module Stage 2 High | B0013 02 | B0013 0D | B0013 04 | B0013 01 | B0013 0E |
Steering Wheel Module Stage 2 Low | 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
| • | When a harness connector is disconnected, the high control and low control circuits are shorted together by the integral shorting bar. This should be taken into account when testing for faults on these circuits. |
| • | This DTC usually indicates a poor connection or a wiring malfunction between the SDM and the deployment loop. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
SIR System Description and Operation
Electrical Information Reference
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 connectors inspect for damage, corrosion or poor connection. Damage or corrosion to 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
- Verify that the steering wheel inflator restraint module connector and CPA are engaged.
- Ignition OFF, disconnect the harness connector at the steering wheel inflator module.
- With the appropriate load tool adaptor, connect J 38715-A in place of the steering wheel inflator module.
- Ignition ON, with a scan tool, verify the appropriate DTC is set as current.
- Ignition OFF, disconnect J 38715-A and the adaptor.
- Disconnect the steering wheel module coil in-line connector.
- With the appropriate load tool adaptor, connect special tool J 38715-A .
- Ignition ON, with a scan tool, verify DTC is set as current.
- Ignition OFF, disconnect special tool J 38715-A and the adaptor.
- Disconnect the harness connector at the SDM.
- Ignition ON, test for less than 1 volt between the appropriate high circuit and ground.
- Test for less than 1 volt between the appropriate low circuit and ground.
- Ignition OFF, test for infinite resistance between the appropriate high circuit and ground.
- Test for infinite resistance between the appropriate low circuit and ground.
- Test for less then 1 ohm between the SDM connector and the air bag module connector high circuit.
- Test for less then 1 ohm between the SDM connector and the air bag module connector low circuit.
- If all circuits test normal, replace the SDM.
| ⇒ | If the above condition is not found, make the appropriate repair. |
| ⇒ | 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. |
| ⇒ | If DTC is not set or is set as history, replace the steering wheel module coil. |
| • | Steering wheel module coil connector Stage 1 terminal A X1 |
| • | Steering wheel module coil connector Stage 2 terminal A X2 |
| ⇒ | If greater than the specified range, test the circuit for a short to voltage. |
| • | Steering wheel module coil connector Stage 1 terminal B X1 |
| • | Steering wheel module coil connector Stage 2 terminal B X2 |
| ⇒ | If greater than the specified range, test the circuit for a short to voltage. |
| • | Steering wheel module coil connector Stage 1 terminal A X1 |
| • | Steering wheel module coil connector Stage 2 terminal A X2 |
| ⇒ | If less than the specified value, test the circuit for a short to ground. |
| • | Steering wheel module coil connector Stage 1 terminal B X1 |
| • | Steering wheel module coil connector Stage 2 terminal B X2 |
| ⇒ | If less than the specified value, test the circuit for a short to ground. |
| • | Steering wheel module coil connector Stage 1 terminal A X1 and SDM terminal 9 |
| • | Steering wheel module coil connector Stage 2 terminal A X2 and SDM terminal 5 |
| ⇒ | If greater than the specified range, test the circuit for an open/high resistance. |
| • | Steering wheel module coil connector Stage 1 terminal B X1 and SDM terminal 8 |
| • | Steering wheel module coil connector Stage 2 terminal B X2 and SDM terminal 4 |
| ⇒ | If greater than the specified range, test the circuit for an open/high resistance. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for SDM replacement, setup, and programming |
