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B0012



DTC B0012-B0044

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* 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
- Passenger Frontal Deployment Loop (Stage 2) Resistance Low

DTC B0013
- Passenger Frontal Deployment Loop (Stage 2) Open

DTC B0014
- Passenger Frontal Deployment Loop (Stage 2) Voltage Out of Range

DTC B0016
- Passenger Frontal Deployment Loop (Stage 1) Resistance Low

DTC B0017
- Passenger Frontal Deployment Loop (Stage 1) Open

DTC B0018
- Passenger Frontal Deployment Loop (Stage 1) Voltage Out of Range

DTC B0022
- Driver Frontal Deployment Loop (single stage or stage 1) Resistance

DTC B0024
- Driver Frontal Deployment Loop (single stage or stage 1) Voltage Out of Range

DTC B0026
- Driver Frontal Deployment Loop (single stage or stage 1) Open

DTC B0042
- Driver Frontal Deployment Loop (stage 2) Resistance Low

DTC B0043
- Driver Frontal Deployment Loop (stage 2) Voltage Out of Range

DTC B0044
- Driver Frontal Deployment Loop (stage 2) Open

Diagnostic Fault Information






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 deployment loop in order to deploy an inflatable restraint module. There are 2 shorting bars used within the module connector which will short together both high and low circuits when the connector is disconnected. This will prevent unwanted deployment of the inflatable restraint module during servicing.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

B0012 Stage 2 or B0016 Stage 1

The DTC will set when the I/P module deployment loop resistance is less than 1.3 ohms for 500 milliseconds.

B0013 Stage 2 or B0017 Stage 1

The DTC will set when one of the following conditions occur:

* The I/P module stage 1 or stage 2 high circuit is less than 2.4 volts and the I/P module stage 1 or stage 2 deployment loop is more than 6 ohms for 500 milliseconds.
* The I/P module stage 1 or stage 2 deployment loop resistance is more than 4.8 ohms for 500 milliseconds.

B0014 Stage 2 or B0018 Stage 1

The DTC will set when one of the following conditions occur:

* The I/P module stage 1 or stage 2 high and/or low circuits is short to ground or short to voltage for 500 milliseconds.
* The I/P module stage 1 or stage 2 high circuit is less than 2.4 volts and I/P module stage 1 or stage 2 deployment loop resistance is less than 6 ohms for 500 milliseconds.

B0022-stage 1 or B0042-stage 2

The DTC will set when the steering wheel module deployment loop resistance is less than 1.3 ohms for 500 milliseconds.

B0024-stage 1 or B0043-stage 2

The DTC will set when one of the following conditions occur:

* The steering wheel module high and/or low circuits is short to ground or short to voltage for 500 milliseconds.
* The steering wheel module high circuit is less than 2.4 volts and the steering wheel module deployment loop resistance is less than 6 ohms for 500 milliseconds.

B0026-stage 1 or B0044-stage 2

The DTC will set when one of the following conditions occurs:

* The steering wheel module high circuit is less than 2.4 volts and the steering wheel module deployment loop is more than 6 ohms for 500 milliseconds.
* The steering wheel module deployment loop resistance is more than 4.8 ohms for 500 milliseconds.

Action Taken When the DTC Sets

* The SDM commands the AIR BAG indicator ON via serial data communications.
* The SIR system is disabled and no deployments are allowed.

Conditions for Clearing the DTC

* The condition responsible for setting the DTC no longer exists.
* A history DTC will clear once 255 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.

Special Tools

* J 38715-A SIR Driver/Passenger Load Tool
* J 38715-80 Driver/Passenger Load Tool Adapter
* EL 38715-120 SIR Load Tool Adapter (Top of Column)
* EL 38715-140 SIR Load Tool Adapter (Back of Steering Wheel Coil)

Circuit/System Testing

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

* The pretensioner

* The inflatable restraint module

* The SDM module

* The inflatable restraint module wiring harness connector

* The SDM wiring harness connector

1. Ignition OFF, disconnect the harness connector at the applicable inflatable restraint module.
2. Ignition ON, test for less than 1 volt between the applicable high control circuit terminal and ground.

* I/P Module - Stage 1 terminal A1
* I/P Module - Stage 2 terminal B1
* Left Front Roof Rail Module terminal B
* Right Front Roof Rail Module terminal B
* Steering Wheel Module - Stage 1 terminal B
* Steering Wheel Module - Stage 2 terminal B
* Seat Belt Pretensioner - Left terminal 2
* Seat Belt Pretensioner - Right terminal 2

^ If greater than the specified range, test both the high control circuit and the low control circuit for a short to voltage. If the circuit tests normal, replace the SDM.

3. Test for less than 1 volt between the applicable low control circuit terminal and ground.

* I/ I/P Module - Stage 1 terminal A2
* I/P Module - Stage 2 terminal B2
* Left Front Roof Rail Module terminal A
* Right Front Roof Rail Module terminal A
* Steering Wheel Module - Stage 1 terminal A
* Steering Wheel Module - Stage 2 terminal A
* Seat Belt Pretensioner - Left terminal 1
* Seat Belt Pretensioner - Right terminal 1

^ If greater than the specified range, test both the high control circuit and the low control circuit for a short to voltage. If the circuit tests normal, replace the SDM.

4. Ignition OFF, test for infinite resistance between the applicable high control circuit terminal and ground.

* I/P Module - Stage 1 terminal A1
* I/P Module - Stage 2 terminal B1
* Left Front Roof Rail Module terminal B
* Right Front Roof Rail Module terminal B
* Steering Wheel Module - Stage 1 terminal B
* Steering Wheel Module - Stage 2 terminal B
* Seat Belt Pretensioner - Left terminal 2
* Seat Belt Pretensioner - Right terminal 2

^ If not the specified value, test both the high control circuit and the low control circuit for a short to ground. If the circuit tests normal, replace the SDM.

5. Test for infinite resistance between the applicable low control circuit terminal and ground.

* I/P Module - Stage 1 terminal A2
* I/P Module - Stage 2 terminal B2
* Left Front Roof Rail Module terminal A
* Right Front Roof Rail Module terminal A
* Steering Wheel Module - Stage 1 terminal A
* Steering Wheel Module - Stage 2 terminal A
* Seat Belt Pretensioner - Left terminal 1
* Seat Belt Pretensioner - Right terminal 1

^ If not the specified value, test both the high control circuit and the low control circuit for a short to ground. If the circuit tests normal, replace the SDM.

6. With the applicable adaptor, connect special tool J 38715-A in place of the inflatable restraint module.
7. Ignition ON, verify the DTC is set as current.

^ If DTC is not set or is set as history, replace the applicable inflatable restraint module.

8. Ignition OFF, disconnect special tool J 38715-A and the applicable adaptor.
9. Disconnect the harness connector at the SDM.
10. Test for less then 1 ohm of resistance between the following high control circuit terminals:

* I/P Module - Stage 1 terminal A1 and SDM terminal 6
* I/P Module - Stage 2 terminal B1 and SDM terminal 10
* Left Front Roof Rail Module terminal A and SDM terminal 13
* Right Front Roof Rail Module terminal A and SDM terminal 14
* Steering Wheel Module - Stage 1 terminal A and SDM terminal 5
* Steering Wheel Module - Stage 2 terminal A and SDM terminal 9
* Seat Belt Pretensioner - Left terminal 1 and SDM terminal 17
* Seat Belt Pretensioner - Right terminal 1 and SDM terminal 18

^ If not within the specified range, test the circuit for an open/high resistance.

11. Test for less then 1 ohm of resistance between the following low control circuit terminals.

* I/P Module - Stage 1 terminal A2 and SDM terminal 7
* I/P Module - Stage 2 terminal B2 and SDM terminal 11
* Left Front Roof Rail Module terminal B and SDM terminal 12
* Right Front Roof Rail Module terminal B and SDM terminal 15
* Steering Wheel Module - Stage 1 terminal B and SDM terminal 4
* Steering Wheel Module - Stage 2 terminal B and SDM terminal 8
* Seat Belt Pretensioner - Left terminal 2 and SDM terminal 16
* Seat Belt Pretensioner - Right terminal 2 and SDM terminal 19

^ If not within the specified range, test the circuit for an open/high resistance.

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

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* SIR/SRS Wiring Repairs
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