Chevrolet Trax: DTC B0017 OR B0024: Knee air bag deployment loop

Diagnostic Instructions

• 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.

DTC Descriptors

DTC B0017 01

Driver Knee Air Bag Deployment Loop Short to Battery

DTC B0017 02

Driver Knee Air Bag Deployment Loop Short to Ground

DTC B0017 04

Driver Knee Air Bag Deployment Loop Open

DTC B0017 0D

Driver Knee Air Bag Deployment Loop High Resistance

DTC B0017 0E

Driver Knee Air Bag Deployment Loop Low Resistance

DTC B0024 01

Passenger Knee Air Bag Deployment Loop Short to Battery

DTC B0024 02

Passenger Knee Air Bag Deployment Loop Short to Battery

DTC B0024 04

Passenger Knee Air Bag Deployment Loop Open

DTC B0024 0D

Passenger Knee Air Bag Deployment Loop High Resistance

DTC B0024 0E

Passenger Knee Air Bag Deployment Loop Low Resistance

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 air bag. There are two shorting bars used within the connector that will short together the control circuits, when the connector is disconnected.

This will help to prevent unwanted deployment of the air bag or retractor pretensioner during servicing.

Conditions for Running the DTC

Ignition voltage is between 9-16 V.

Conditions for Setting the DTC

B0017 01, B0024 01

The air bag control circuit is shorted to voltage for 2 seconds.

B0017 02, B0024 02

The air bag control circuit is shorted to ground for 2 seconds.

B0017 04, B0024 04

The air bag control circuit is open for 2 seconds.

B0017 0D, B0024 0D

The air bag deployment loop resistance is greater than 4.2 ohms for 2 seconds.

B0017 0E, B0024 0E

The air bag deployment loop resistance is less than 1.4 ohms for 2 seconds.

Action Taken When the DTC Sets

• The Inflatable Restraint Sensing and Diagnostic Module requests the instrument cluster to illuminate the AIR BAG indicator.
• The Inflatable Restraint Sensing and Diagnostic Module will store a DTC, however if an event occurs the system will still attempt deployments.

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.

Diagnostic Aid

NOTE: The following diagnostic aids apply for both current and history DTCs.

An incorrectly installed connector position assurance (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 and passenger knee air bags
• Inline harness connectors
• Harness side of the inflatable restraint sensing and diagnostic module 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.

Reference Information

Schematic Reference

SIR Schematics (Encore), SIR Schematics (Trax)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX - TRAX

Component Connector End Views (Encore) , Component Connector End Views (Trax)

Description and Operation

Supplemental Inflatable Restraint System Description and Operation

Electrical Information Reference

• Circuit Testing
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs
• Connector Repairs

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-38125-580 Terminal Release Tool Kit

Circuit/System Verification

NOTE:

• Refer to SIR Service Precautions.
• 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.

• Knee air bag
• Inflatable restraint sensing and diagnostic module
• All wiring harness connectors
• Inflatable restraint sensing and diagnostic module 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.
• If the condition is intermittent or cannot be duplicated, disconnect the connectors and add dielectric grease/lubricant (Nyogel 760G or equivalent, meeting GM specification 9986087). This procedure will correct the high resistance condition due to terminal fretting corrosion.

1. Verify the scan tool Deployment Loop Resistance parameters stay consistently between 2.1 and 4.0 ohms without any spikes or dropouts while moving the harness near each connector listed below:

• F114D Knee Air Bag - Driver
• F114P Knee Air Bag - Passenger
• Any inline harness connector
• K36 Inflatable Restraint Sensing and Diagnostic Module
• If less than 2.1 or greater than 4.0 ohms

Refer to Circuit/System Testing.

• If there are spikes or dropouts, perform the following:
• Inspect each connector terminal and harness for damage or corrosion and repair as necessary.
• Apply dielectric grease/lubricant (Nyogel 760G or equivalent, meeting GM specification 9986087) to each connector terminal
• Ensure each connector and CPA is correctly seated
• If between 2.1 and 4.0 ohms without any spikes or dropouts

2. All OK

Circuit/System Testing

1. Ignition OFF, disconnect the scan tool and disconnect the harness connector at the appropriate F114 Knee Air Bag.
2. Test for greater than 25 ohms between the control circuit terminals 1 and 2.

• If 25 ohms or less

1. Disconnect the X1 harness connector at the K36 Inflatable Restraint Sensing and Diagnostic Module.

NOTE: Some connectors may be equipped with shorting bars as a safety component to prevent accidental inflator deployment. When testing on a connector with shorting bars, the shorting bars must be disabled to ensure accurate test results. Insert an appropriate pick from EL-38125-580 and depress the shorting bars above the appropriate terminals. This will lift the shorting bar from the terminal and allow accurate test results. Take care not to damage the connector, shorting bar, or terminal when depressing the shorting bar.

2. Test for infinite resistance between the 2 control circuits.

• If less than infinite resistance, repair the short between the 2 circuits.
• If infinite resistance, replace the K36 Inflatable Restraint Sensing and Diagnostic Module.
• If greater than 25 ohms

3. Ignition ON.
4. Test for less than 11 V between the control circuit terminals listed below and ground:

• Control circuit terminal 1
• Control circuit terminal 2
• If 11 V or greater

1. Ignition OFF, disconnect the X1 harness connector at the K36 Inflatable Restraint Sensing and Diagnostic Module, ignition ON.
2. Test for less than 1 V between the control circuit and ground.

• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K36 Inflatable Restraint Sensing and Diagnostic Module.
• If less than 11 V

5. Ignition OFF.
6. Test for greater than 25 ohms between the control circuit terminals listed below and ground:

• Control circuit terminal 1
• Control circuit terminal 2
• If 25 ohms or less

1. Disconnect the X1 harness connector at the K36 Inflatable Restraint Sensing and Diagnostic Module.
2. Test for infinite resistance between the control circuit and ground.

• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, replace the K36 Inflatable Restraint Sensing and Diagnostic Module.
• If greater than 25 ohms

7. Install a 3 A fused jumper wire between the control circuit terminals 1 and 2, ignition ON.
8. Verify DTC B0017 0E or B0024 0E is set

• If B0017 0E or B0024 0E is not set

1. Ignition OFF, disconnect the X1 harness connector at the K36 Inflatable Restraint Sensing and Diagnostic Module.
2. Test for less than 2 ohms in each control circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K36 Inflatable Restraint Sensing and Diagnostic Module.
• If B0017 0E or B0024 0E is set

9. Ignition OFF, connect the harness connector at the F114 Knee Air Bag, press in the CPA (if equipped) until an audible and/or tactile click is heard.
10. Ignition ON, clear DTCs. Operate the vehicle within the Conditions for Running the DTC.
11. Verify DTC B0017 or B0024 is not set.

• If DTC B0017 or B0024 is set

Replace the appropriate F114 Knee Air Bag.

• If DTC B0017 or B0024 is not set

12. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Instrument Panel Lower Airbag Replacement - Driver Side (AYF)
• Instrument Panel Lower Airbag Replacement - Passenger Side (AYF)
• Control Module References for K36 Inflatable Restraint Sensing and Diagnostic Module replacement, programming, and setup

READ NEXT: