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B0018




DTC B0012, B0013, B0014, B0016, B0017, or B0018

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
- Passenger Instrument Panel Air Bag Deployment Loop Stage 2 Resistance Low

DTC B0013
- Passenger Instrument Panel Air Bag Deployment Loop Stage 2 Open

DTC B0014
- Passenger Instrument Panel Air Bag Deployment Loop Stage 2 Voltage Out of Range

DTC B0016
- Passenger Instrument Panel Air Bag Deployment Loop Stage 1 Resistance Low

DTC B0017
- Passenger Instrument Panel Air Bag Deployment Loop Stage 1 Open

DTC B0018
- Passenger Instrument Panel Air Bag Deployment Loop Stage 1 Voltage Out of Range

Diagnostic Fault Information






Circuit/System Description

The passenger deployment loop consists of a dual stage passenger instrument panel air bag. The passenger instrument panel air bag high circuits, and the passenger instrument panel air bag low circuits exist for both stages 1 and 2. There are 2 shorting bars used within the passenger instrument panel air bag connector. These shorting bars short together the passenger instrument panel air bag stage 1 high circuits, and low circuits, and the passenger instrument panel air bag stage 2 high circuits and low circuits when the connector is disconnected. This prevents unwanted deployment of the air bag during servicing. During a frontal crash of sufficient force the inflatable restraint sensing and diagnostic module (SDM) will allow current to flow through the deployment loop. This flow of current will deploy the passenger instrument panel 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. If a malfunction is detected, a diagnostic trouble code (DTC) will be stored in memory.

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 passenger instrument panel air bag deployment loop resistance is less than 1.3 ohms for 500 milliseconds.

B0013 stage 2 or B0017 stage 1
* The passenger instrument panel air bag stage 1 or stage 2 high circuit is less than 2.4 volts and the passenger instrument panel air bag stage 1 or stage 2 deployment loop is more than 6 ohms for 500 milliseconds.
* The passenger instrument panel air bag stage 1 or stage 2 deployment loop resistance is greater than 4.8 ohms for 500 milliseconds.

B0014 stage 2 or B0018 stage 1
* The passenger instrument panel air bag stage 1 or stage 2 high and/or low circuits are shorted to voltage or shorted to ground for 500 milliseconds.
* The passenger instrument panel air bag stage 1 or stage 2 high circuit is less than 2.4 volts and passenger instrument panel air bag stage 1 or stage 2 deployment loop resistance is less than 6 ohms for 500 milliseconds.

Action Taken When the DTC Sets

* The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.
* The SIR system is disabled and no deployments are allowed.

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.

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
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module References for scan tool information
Special Tools

J 38715-A Driver/Passenger Load tool

Circuit/System Testing

Important: Refer to SIR Service Precautions Technician Safety Information.


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


* Passenger instrument panel air bag

* SDM

* Passenger instrument panel air bag wiring harness connector

* SDM wiring harness connector


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.


1. Verify that the appropriate air bag connector and CPA are engaged.

• If the above condition is not found, make the appropriate repair.

2. Ignition OFF, disconnect the harness connector at the passenger instrument panel air bag.
3. With the appropriate load tool adaptor, connect special tool J 38715-A in place of the passenger instrument panel air bag.
4. Ignition ON, with a scan tool, verify the appropriate DTC is set as current.

• 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 passenger instrument panel air bag, and cycle the ignition ON. If the DTC resets after reconnecting the passenger instrument panel air bag, replace the passenger instrument panel air bag.

5. Ignition OFF, disconnect special tool J 38715-A and the adaptor.
6. Disconnect the harness connector at the SDM.
7. Ignition ON, test for less than 1 volt between the appropriate high control circuit listed below and ground:

* SDM Stage 1 terminal 9
* SDM Stage 2 terminal 30

• If greater than the specified value, test the high control circuit for a short to voltage.

8. Test for less than 1 volt between the appropriate low control circuit terminal listed below and ground:

* SDM Stage 1 terminal 10
* SDM Stage 2 terminal 31

• If greater than the specified value, test the low control circuit for a short to voltage.

9. Ignition OFF, test for infinite resistance between the appropriate high control circuit terminal listed below and ground:

* SDM Stage 1 terminal 9
* SDM Stage 2 terminal 30

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

10. Test for infinite resistance between the appropriate low control circuit terminal listed below and ground:

* SDM Stage 1 terminal 10
* SDM Stage 2 terminal 31

• If not the specified value, test the low control circuit for a short to ground.

11. Test for less then 1 ohm between the following high control circuit terminals listed below:

* I/P module Stage 1 terminal 4 and SDM terminal 9
* I/P module Stage 2 terminal 2 and SDM terminal 30

• If greater than the specified range, test the high control circuit for an open/high resistance.

12. Test for less then 1 ohm between the following low control circuit terminals listed below:

* Passenger instrument panel air bag Stage 1 terminal 3 and SDM terminal 10
* Passenger instrument panel air bag Stage 2 terminal 1 and SDM terminal 31

• If greater than the specified range, test the low control circuit for an open/high resistance.

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

Repair Instructions

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

* Instrument Panel Inflatable Restraint Module Replacement Instrument Panel Inflatable Restraint Module Replacement
* Control Module References Control Module References for SDM replacement, setup, and programming

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