B0013
DTC B0012 or B0013
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category
DTC Descriptors
DTC B0012 01
- Driver Steering Wheel Air Bag Deployment Loop Stage 1 Short to Battery
DTC B0012 02
- Driver Steering Wheel Air Bag Deployment Loop Stage 1 Short to Ground
DTC B0012 04
- Driver Steering Wheel Air Bag Deployment Loop Stage 1 Open
DTC B0012 0D
- Driver Steering Wheel Air Bag Deployment Loop Stage 1 High Resistance
DTC B0012 0E
- Driver Steering Wheel Air Bag Deployment Loop Stage 1 Low Resistance
DTC B0013 01
- Driver Steering Wheel Air Bag Deployment Loop Stage 2 Short to Battery
DTC B0013 02
- Driver Steering Wheel Air Bag Deployment Loop Stage 2 Short to Ground
DTC B0013 04
- Driver Steering Wheel Air Bag Deployment Loop Stage 2 Open
DTC B0013 0D
- Driver Steering Wheel Air Bag Deployment Loop Stage 2 High Resistance
DTC B0013 0E
- Driver Steering Wheel Air Bag Deployment Loop Stage 2 Low Resistance
Diagnostic Fault Information
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 driver steering wheel air bag. 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 driver steering wheel air bag coil connector which will short together both driver steering wheel air bag stage 1 high circuit and driver steering wheel air bag stage 1 low circuit and both driver steering wheel air bag stage 2 high circuit and driver steering wheel air bag stage 2 low circuit when the connector is disconnected. This will help to prevent unwanted deployment of the driver steering wheel air bag during servicing.
Conditions for Running the DTC
Ignition voltage is between 9-16 V.
Conditions for Setting the DTC
B0012 01 stage 1 or B0013 01 stage 2
The driver steering wheel air bag deployment loop is shorted to voltage for 2 seconds.
B0012 02 stage 1 or B0013 02 stage 2
The driver steering wheel air bag deployment loop is shorted to ground for 2 seconds.
B0012 04 stage 1 or B0013 04 stage 2
The driver steering wheel air bag deployment loop is open for 2 seconds.
B0012 0D stage 1 or B0013 0D stage 2
The driver steering wheel air bag deployment loop resistance is greater than 4.4 ohm for 2 seconds.
B0012 0E stage 1 or B0013 0E stage 2
The driver steering wheel air bag deployment loop resistance is less than 1.7 ohm for 2 seconds.
Action Taken When the DTC Sets
* The SDM requests the instrument cluster to illuminate the AIR BAG indicator.
* The SDM will store a DTC, however if an event occurs the system will still attempt deployment.
Conditions for Clearing the DTC
* The condition for setting the DTC is no longer exists.
* A history DTC will clear once 100 malfunction-free ignition cycles have occurred.
Diagnostic Aid
Note: The following diagnostic aids apply for both current and history DTCs.
A worn driver steering wheel air bag coil can cause a repeated history DTC to set. To verify this condition, turn the steering wheel 360 degrees in one direction then back 360 degrees in the other direction, multiple times, while viewing the scan tool Deployment Loop Resistance 1 and 2 parameters.
An incorrectly installed CPA or incorrectly seated connector can cause a shorting bar to short both control circuits together. Check the connectors and CPAs if a DTC with symptom byte 02 or 0E is set, to ensure the shorting bars are not causing the circuits to be shorted together. Shorting bars are used in the locations listed below:
* Driver steering wheel air bag
* Driver steering wheel air bag coil
* SDM
* Inline connectors - on the steering wheel air bag side of the harness connector
* Harness side of the SDM connector
Terminal fretting or incorrectly seated connector can cause an open/high resistance condition. Check the circuit terminals for fretting or incorrectly seated connector if a DTC with symptom byte 04 or 0D is set.
If the steering wheel air bag has inflated under unexpected conditions and/or DTC with symptom byte 01 is set, check both control circuits for a short to voltage.
Reference Information
Schematic Reference
SIR Schematics ([1][2]Air Bag Systems)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
Description and Operation
SIR System Description and Operation (Description and Operation)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Testing for Intermittent Conditions and Poor Connections (Testing For Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
* Connector Repairs (Connector Repairs)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Verification
Note: Refer to SIR Service Precautions (Technician Safety Information).
Inspect all terminals for damage or corrosion when disconnecting connectors. Damage or corrosion in the following requires repair or replacement of the affected component/connector.
* Driver Steering Wheel Air bag
* Driver steering wheel air bag coil
* SDM
* Air bag wiring harness connector
* SDM wiring harness connector
Note: 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.
If the condition is intermittent or cannot be duplicated, disconnect the connectors and add Nyogel lubricant 760G. This procedure will correct the high resistance condition due to terminal fretting corrosion.
1. Observe the scan tool Deployment Loop Resistance 1 and 2 parameters while turning the steering wheel 360 degrees in one direction then back 360 degrees in the other direction. The reading should stay consistently between 2.1 and 4.0 ohm without any spikes or dropouts.
• If the reading is erratic while turning the steering wheel, replace the X85 driver steering wheel air bag coil.
• If not within the specified range, refer to Circuit/System Testing.
2. DTC B0012 or B0013 should only be set as a history DTC.
• If the DTC is set as current, refer to Circuit/System Testing.
3. Observe the scan tool Deployment Loop Resistance 1 and 2 parameters while moving the harness near each connector listed below. The reading should stay consistently between 2.1 and 4.0 ohm without any drop outs or spikes.
* X85 Steering wheel air bag coil
* F107 Steering wheel air bag.
* Any harness inline
* K36 SDM
• If the reading is erratic while moving the harness, perform the following:
* Inspect each connector terminal for damage or corrosion and repair as necessary.
* Apply Nyogel lubricant 760G to each connector terminal.
* Insure each connector and CPA is correctly seated.
Circuit/System Testing
1. Ignition OFF, disconnect the scan tool and disconnect the harness connector at the F107 driver steering wheel air bag.
2. Wait for 120 seconds and then test for greater than 25 ohm between the control circuit terminal 1 and the control circuit terminal 2.
• If less than the specified range, test for a short between the control circuits, check each connector and CPA to ensure the shorting bars are lifted. If the circuits and shorting bars tests normal, replace the K36 SDM.
3. Ignition ON, test for less than 11 V between the control circuit terminals listed below and ground:
* Control circuit terminal 1
* Control circuit terminal 2
• If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the K36 SDM.
4. Ignition OFF, test for greater than 25 ohm between the control circuit terminals listed below and ground:
* Control circuit terminal 1
* Control circuit terminal 2
• If less than the specified range, test the driver steering wheel air bag coil for a short to ground and the control circuit for a short to ground. If the circuit tests normal, replace the K36 SDM.
5. Install a 3 A fused jumper wire between the control circuit terminal 1 and the control circuit terminal 2.
6. Ignition ON, observe the scan tool Deployment Loop Resistance parameter while turning the steering wheel 360 degrees in one direction then back 360 degrees in the other direction. Verify the scan tool Deployment Loop Resistance parameter is consistently less than 2 ohm.
• If the reading is erratic while turning the steering wheel, replace the X85 driver steering wheel airbag coil.
• If greater than the specified range, test the driver steering wheel airbag coil and the control circuit terminals 1 and 2 for an open/high resistance. If the driver steering wheel air bag coil and the control circuits test normal, replace the K36 SDM.
7. If all circuits test normal, replace the F107 driver steering wheel air bag.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Steering Wheel Inflatable Restraint Module Coil Replacement (Removal and Replacement)
* Steering Wheel Inflatable Restraint Module Airbag Replacement (Steering Wheel Inflatable Restraint Module Airbag Replacement)
* SIR/SRS Wiring Repairs (SIR/SRS Wiring Repairs)
* Control Module References (Programming and Relearning) for SDM replacement, setup, and programming