B0087

DTC B0083-B0088

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 B0083 01
- Left Front Impact Sensor Short to Battery

DTC B0083 02
- Left Front Impact Sensor Short to Ground

DTC B0083 05
- Left Front Impact Sensor Short to Battery or Open

DTC B0083 0F
- Left Front Impact Sensor Erratic

DTC B0083 39
- Left Front Impact Sensor Internal Electronic Failure

DTC B0083 3A
- Left Front Impact Sensor Incorrect Component Installed

DTC B0083 71
- Left Front Impact Sensor Invalid Serial Data Received

DTC B0084 01
- Right Front Impact Sensor Short to Battery

DTC B0084 02
- Right Front Impact Sensor Short to Ground

DTC B0084 05
- Right Front Impact Sensor Short to Battery or Open

DTC B0084 0F
- Right Front Impact Sensor Erratic

DTC B0084 39
- Right Front Impact Sensor Internal Electronic Failure

DTC B0084 3A
- Right Front Impact Sensor Incorrect Component Installed

DTC B0084 71
- Right Front Impact Sensor Invalid Serial Data Received

DTC B0085 01
- Left Front Side Impact Sensor Short to Battery

DTC B0085 02
- Left Front Side Impact Sensor Short to Ground

DTC B0085 05
- Left Front Side Impact Sensor Short to Battery or Open

DTC B0085 0F
- Left Front Side Impact Sensor Erratic

DTC B0085 39
- Left Front Side Impact Sensor Internal Electronic Failure

DTC B0085 3A
- Left Front Side Impact Sensor Incorrect Component Installed

DTC B0085 71
- Left Front Side Impact Sensor Invalid Serial Data Received

DTC B0086 01
- Right Front Side Impact Sensor Short to Battery

DTC B0086 02
- Right Front Side Impact Sensor Short to Ground

DTC B0086 05
- Right Front Side Impact Sensor Short to Battery or Open

DTC B0086 0F
- Right Front Side Impact Sensor Erratic

DTC B0086 39
- Right Front Side Impact Sensor Internal Electronic Failure

DTC B0086 3A
- Right Front Side Impact Sensor Incorrect Component Installed

DTC B0086 71
- Right Front Side Impact Sensor Invalid Serial Data Received

Diagnostic Fault Information





Circuit/System Description

The impact sensor utilizes a bidirectional 2-wire circuit. The impact sensor modulates current on the interface to send ID, state of health, and deployment commands to the inflatable restraint sensing and diagnostic module (SDM). The SDM serves as a power source and a ground for the impact sensor. When the ignition is turned ON and input power from the SDM is first detected, the impact sensor responds by performing internal diagnostics and sending an ID to the SDM. The SDM considers the ID to be valid if the response time is less than 5 seconds. The impact sensor continually communicates status messages to the SDM, which determines if a fault is present in the impact sensor circuit. When a fault is detected, the SDM may reset the impact sensor up to 2 times by removing and reapplying power to it. If the fault is still present, the SDM will set a DTC.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

Any of the following conditions exist for 2.5 seconds:

B0083 01, B0084 01, B0085 01, B0086 01

The impact sensor has been shorted to voltage.

B0083 02, B0084 02, B0085 02, B0086 02
* The impact sensor has been shorted to ground.
* The impact sensor current is greater than 23 mA for greater than 5 milliseconds.

B0083 05 or B0084 05, B0085 05, B0086 05
* The impact sensor has been shorted to voltage.
* The impact sensor circuit is open.
* The SDM has not received a message from the impact sensor for greater than 375 milliseconds.

B0083 0F, B0084 0F, B0085 0F, B0086 0F

The SDM has received erratic messages from the impact sensor.

B0083 39, B0084 39, B0085 39, B0086 39
* The SDM has received a Not OK (NOK) message from the impact sensor.
* The SDM has not received a message.

B0083 3A, B0084 3A, B0085 3A, B0086 3A
* The SDM has received an ID message from the impact sensor, which does not match the ID stored in the SDM memory.
* The SDM has reset the impact sensor twice without detecting the correct ID message.

B0083 71, B0084 71, B0085 71, B0086 71

The SDM has received invalid serial data from the impact sensor.

Action Taken When the DTC Sets

* The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.
* SIR 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 (SIR System)
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 (Programming and Relearning) for scan tool information

Circuit/System Testing

Important: Refer to SIR Service Precautions (Technician Safety Information).


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


* Impact sensor

* SDM

* Impact sensor wiring harness connector

* SDM wiring harness connector


1. Ignition OFF, disconnect the harness connector at the SDM and the appropriate impact sensor.
2. Ignition ON, test for less than 1 volt between the signal circuit of the impact sensor 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 low reference circuit of the impact sensor 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 signal circuit terminal B and ground.

• If less than infinite resistance, test the circuit for a short to ground.

5. Test for less than 1 ohm between the following signal circuit terminals.

* Left front impact sensor terminal B and SDM harness connector terminal 36.
* Right front impact sensor terminal B and SDM harness connector terminal 37.
* Left front side impact sensor terminal B and the SDM harness connector terminal 42.
* Right front side impact sensor terminal B and the SDM harness connector terminal 43.

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

6. Test for less then 1 ohm between the following low reference circuit terminals.

* Left front impact sensor terminal A and SDM harness connector terminal 38.
* Right front impact sensor terminal A and SDM harness connector terminal 39.
* Left front side impact sensor terminal A and the SDM harness connector terminal 40.
* Right front side impact sensor terminal A and the SDM harness connector terminal 41.

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

7. If all circuits test normal, replace the appropriate 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 SDM.

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)
* Inflatable Restraint Side Impact Sensor Replacement (Impala) (Inflatable Restraint Side Impact Sensor Replacement)
* SIR/SRS Wiring Repairs (SIR/SRS Wiring Repairs)
* Control Module References (Programming and Relearning) for SDM replacement, setup, and programming