Diagnostic Instructions

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 04	B0012 01	B0012 0E
Steering Wheel Module Stage 1 Low Control	B0012 02	B0012 0D, B0012 04	B0012 04	B0012 01	B0012 0E
Steering Wheel Module Stage 2 High Control	B0013 02	B0013 0D, B0013 04	B0013 04	B0013 01	B0013 0E
Steering Wheel Module Stage 2 Low Control	B0013 02	B0013 0D, B0013 04	B0013 04	B0013 01	B0013 0E

Circuit/System Description

During a side or frontal crash of sufficient force, the inflatable restraint sensing and diagnostic module (SDM) will allow current to flow through the appropriate deployment loop in order to deploy the steering wheel inflator module at the correct stage. Shorting bars are located in the electrical connectors of both the stage 1 deployment loop and the stage 2 deployment loop of the steering wheel module. The steering wheel module high control circuit and low control circuit are shorted together by the shorting bar when the electrical connector is disconnected. The shorting bars help prevent unwanted deployment of the inflator module during servicing.

The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. If the results of any deployment loop circuit test is below specification, DTC B0012 or B0013 and the appropriate symptom byte sets.

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 short to voltage for 120 milliseconds.

B0012 02 Stage 1 or B0013 02 Stage 2

The steering wheel module high and/or low circuit is short 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

Conditions for Clearing the DTC

Diagnostic Aids

If DTC B0012 0E or B0013 0E is setting, be certain that all circuit shorting bars are isolated after connecting circuit components. There are shorting bars in most circuit connectors, including the SDM and inline harness connectors. DTC B0012 0E or B0013 0E will set if the shorting bars are engaged when the ignition is ON.

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

Scan Tool Reference

Control Module References for scan tool information

Special Tools

Circuit/System Testing

Important: When removing the connectors, inspect for terminal damage or corrosion. Inspect the connector body for damage to the locators that disengage the shorting bars when connected. Damage or corrosion to the following components requires repair or replacement of the affected component/connector:

•	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. Correct connection isolates the shorting-bars within the connector allowing the deployment circuit to operate properly.

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

⇒	If the above condition is not 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 or SA9409Z-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 load tool and adaptor, reconnect the harness connector at the steering wheel module, and cycle the ignition ON. If the DTC resets after reconnecting the module, replace the steering wheel module.

5. Ignition OFF, disconnect the load tool and adaptor.
6. Disconnect the X1 harness connector at the steering wheel module coil.
7. With the appropriate load tool adapter, connect special tool J 38715-A or SA9409Z-A in place of the steering wheel module coil.
8. Ignition ON, verify DTC is set as current.

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

9. Ignition OFF, disconnect the load tool and the adaptor.
10. Ignition ON, test for less than 1-volt between the appropriate control circuit listed below and ground:

•	Stage 1 terminal 1 X1 harness connector at the steering wheel module coil

•	Stage 1 terminal 2 X1 harness connector at the steering wheel module coil

•	Stage 2 terminal 3 X1 harness connector at the steering wheel module coil

•	Stage 2 terminal 4 X1 harness connector at the steering wheel module coil

⇒	If not the specified range, test the high control circuit for a short to voltage.

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

•	Stage 1 terminal 1 X1 harness connector at the steering wheel module coil

•	Stage 1 terminal 2 X1 harness connector at the steering wheel module coil

•	Stage 2 terminal 3 X1 harness connector at the steering wheel module coil

•	Stage 2 terminal 4 X1 harness connector at the steering wheel module coil

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

12. Disconnect the harness connector at the SDM.
13. Test for less then 1 ohm between the appropriate control circuit terminals listed below:

•	Stage 1 steering wheel module coil terminal 1 X1 and SDM terminal 15

•	Stage 1 steering wheel module coil terminal 2 X1 and SDM terminal 14

•	Stage 2 steering wheel module coil terminal 3 X1 and SDM terminal 16

•	Stage 2 steering wheel module coil terminal 4 X1 and SDM terminal 17

⇒	If not the specified range, test the high control circuit for an open/high resistance.

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

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.