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B0100




DTC B0100, B0101, B0102, B0103, B0104, or B0105

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 B0100
- Left Front Impact Sensor Performance

DTC B0101
- Discard Electronic Left Front Impact Sensor

DTC B0102
- Incorrect Electronic Left Front Impact Sensor Installed

DTC B0103
- Electronic Right Front Impact Sensor Performance

DTC B0104
- Discard Electronic Right Front Impact Sensor

DTC B0105
- Incorrect Electronic Right Front Impact Sensor Installed

Diagnostic Fault Information






Circuit/System Description

The front impact sensor utilizes a unidirectional 2-wire circuit. The front impact sensor modulates current on the interface to send ID, state of health, and deployment commands to the Inflatable Restraint Sensing and Diagnostic Module. The Inflatable Restraint Sensing and Diagnostic Module serves as a power source and a ground for the front impact sensor. When the ignition is turned ON and input power from the Inflatable Restraint Sensing and Diagnostic Module is first detected, the front impact sensor will respond by performing internal diagnostics and sending an ID to the Inflatable Restraint Sensing and Diagnostic Module. The Inflatable Restraint Sensing and Diagnostic Module considers the ID to be valid if the response time is less than 5 seconds. The front impact sensor continually communicates status messages to the Inflatable Restraint Sensing and Diagnostic Module, which determines if a fault is present in the front impact sensor circuit. When a fault is detected, the Inflatable Restraint Sensing and Diagnostic Module resets the front impact sensor twice by removing and reapplying power. If the fault is still present, the Inflatable Restraint Sensing and Diagnostic Module will set a diagnostic trouble code (DTC).

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

B0100 and B0103

* A valid ID message is not received within 5 seconds of the front impact sensor being powered up.

* Status message is not received.

* The Inflatable Restraint Sensing and Diagnostic Module has failed twice to reset the front impact sensor.

B0102 and B0105

* The Inflatable Restraint Sensing and Diagnostic Module has received an ID message from the front impact sensor that does not match the ID stored in the Inflatable Restraint Sensing and Diagnostic Module memory.

* When 2 front impact sensor resets are attempted without the correct identification being detected by the Inflatable Restraint Sensing and Diagnostic Module.

B0101 and B0104

Will set when the Inflatable Restraint Sensing and Diagnostic Module has received a NOK (Not OK) message from the front impact sensor.

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 attempts to reset the front impact sensor.

Conditions for Clearing the DTC

* The condition responsible 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 5 Bow Lowered Switch (CM7)

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

* Connector Repairs Connector Repairs

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Testing

Note: 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:

* Front impact sensor

* Inflatable Restraint Sensing and Diagnostic Module

* Front impact sensor wiring harness connector

* Inflatable Restraint Sensing and Diagnostic Module wiring harness connector

1. Ignition OFF, disconnect the harness connector at the Inflatable Restraint Sensing and Diagnostic Module and the appropriate front impact sensor.

2. Ignition ON, test for less than 1-volt between the front impact sensor signal circuit terminal B and ground.

If greater than the specified range, test the circuit for a short to voltage.

3. Ignition ON, test for less than 1-volt between the front impact sensor low reference circuit terminal A and ground.

If greater than the specified range, test the circuit for a short to voltage.

4. Test for infinite resistance between the front impact sensor signal circuit terminal B and ground.

If less than the specified value, test the circuit for a short to ground.

5. Test for less than 1 ohm between the front impact sensor signal circuit terminals listed below:

* Right front impact sensor terminal B and Inflatable Restraint Sensing and Diagnostic Module harness connector terminal 6.

* Left front impact sensor terminal B and Inflatable Restraint Sensing and Diagnostic Module harness connector terminal 5.

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

6. Test for less than 1 ohm between the front impact sensor low reference circuit terminals listed below:

* Right front impact sensor terminal A and Inflatable Restraint Sensing and Diagnostic Module harness connector terminal 39.

* Left front impact sensor terminal A and Inflatable Restraint Sensing and Diagnostic Module harness connector terminal 38.

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

7. If all circuits test normal, replace the appropriate front impact sensor.

8. Reconnect all SIR components. Ignition ON, verify the DTC does not set as current.

If the DTC resets as current , replace the Inflatable Restraint Sensing and Diagnostic Module.

Repair Instructions

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

* Inflatable Restraint Front End Sensor Replacement Inflatable Restraint Front End Sensor Replacement

* SIR/SRS Wiring Repairs SIR/SRS Wiring Repairs

* Control Module References Control Module References for Inflatable Restraint Sensing and Diagnostic Module replacement, setup, and programming