• | 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. |
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 |
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.
Ignition voltage is between 9-16 volts.
Any of the following conditions must exist for 1 second:
The steering wheel module high and/or low circuit is shorted to voltage.
The steering wheel module high and/or low circuit is shorted to ground.
The steering wheel module high and/or low circuit is open.
The steering wheel module deployment loop resistance is greater than 3.9 ohms.
The steering wheel module deployment loop resistance is less than 2.1 ohms.
An inflatable restraint module deployment loop high or low control circuit is shorted to another deployment loop high or low control circuit.
• | 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. |
• | The condition for setting the DTC no longer exists. |
• | A history DTC will clear once 100 malfunction-free ignition cycles have occurred. |
SIR System Description and Operation
Control Module References for scan tool information
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.
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.
⇒ | If the above condition is not found, make the appropriate repair. |
⇒ | 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. |
⇒ | 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. |
⇒ | If greater than the specified range, test the high control circuit for a short to voltage. |
⇒ | If greater than the specified range, test the low control circuit for a short to voltage. |
⇒ | If less than the specified value, test the high control circuit for a short to 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.
⇒ | If not within the specified value, replace the steering wheel module. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for SDM replacement, setup, and programming |