GM Service Manual Online
For 1990-2009 cars only

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 B0083 02: Front End Sensor 1 Short to Ground (Left)

DTC B0083 05: Front End Sensor 1 Short to Battery or Open (Left)

DTC B0083 0F: Front End Sensor 1 Erratic (Left)

DTC B0083 39: Front End Sensor 1 Internal Electronic Failure (Left)

DTC B0083 3A: Front End Sensor 1 Incorrect Component Installed (Left)

DTC B0083 71: Front End Sensor 1 Invalid Serial Data Received (Left)

DTC B0084 02: Front End Sensor 2 Short to Ground (Right)

DTC B0084 05: Front End Sensor 2 Short to Battery or Open (Right)

DTC B0084 0F: Front End Sensor 2 Erratic (Right)

DTC B0084 39: Front End Sensor 2 Internal Electronic Failure (Right)

DTC B0084 3A: Front End Sensor 2 Incorrect Component Installed (Right)

DTC B0084 71: Front End Sensor 2 Invalid Serial Data Received (Right)

Diagnostic Fault Information

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

Left Front Discriminating Sensor Signal Circuit

B0083 02

B0083 0F

B0083 05

B0083 05

B0083 0F

Left Front Discriminating Low Reference Circuit

B0083 02

B0083 0F

B0083 05

B0083 05

B0083 0F

Right Front Discriminating Sensor Signal Circuit

B0084 02

B0084 0F

B0084 05

B0084 05

B0084 0F

Right Front Discriminating Low Reference Circuit

B0084 02

B0084 0F

B0084 05

B0084 05

B0084 0F

Circuit/System Description

The inflatable restraint front end sensor utilizes a unidirectional 2-wire circuit. The front end 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 front end sensor. When the ignition is turned ON and input power from the SDM is first detected, the front end 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 front end sensor continually communicates status messages to the SDM, which determines if a fault is present in the front end sensor circuit. When a fault is detected, the SDM may reset the front end 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

All of the following conditions exist for 2.5 seconds:

B0083 02 or B0084 02

    • The front end sensor has been shorted to ground.
    • The front end sensor current has been above 23 mA for longer than 5 milliseconds.

B0083 05 or B0084 05

    • The front end sensor has been shorted to voltage.
    • The front end sensor circuit is open.
    • The SDM has not received a message from the front end sensor for more than 375 milliseconds.

B0083 0F or B0084 0F

The SDM has received erratic messages from the front end sensor.

B0083 39 or B0084 39

    • The SDM has received a NOK message from the front end sensor.
    • The SDM has not received a message.

B0083 3A or B0084 3A

    • The SDM has received an ID message from the front end sensor, which does not match the ID stored in the SDM memory.
    • The SDM has reset the front end sensor twice without detecting the correct ID message.

B0083 71 or B0084 71

The SDM has received invalid serial data from the front end sensor.

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 and the scan tool Clear DTCs function is used.
    • A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

Reference Information

Schematic Reference

SIR Schematics

Connector End View Reference

SIR Connector End Views

Electrical Information Reference

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

Circuit/System Testing

    Important: Refer to SIR Service Precautions

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

       • The front end sensor
       • The SDM module
       • The front end sensor wiring harness connector
       • The SDM wiring harness connector

  1. Ignition OFF, disconnect the appropriate front end sensor connector. Refer to front end sensor replacement for location of connector.
  2. Remove the SDM connector. Refer to SDM replacement for location of connector.
  3. Test for infinite resistance between the signal circuit and ground.
  4. If less than infinite resistance, test the circuit for a short to ground.
  5. Ignition ON, test for less than 1 volt between the front end sensor signal circuit and ground.
  6. If greater than the specified range, test the circuit for a short to voltage.
  7. Ignition ON, test for less than 1 volt between the front end sensor low reference circuit and ground.
  8. If greater than the specified range, test the circuit for a short to voltage.
  9. Test for less then 1 ohm of resistance between the signal circuit front end sensor connector and SDM connector.
  10. If greater than the specified range, test the circuit for an open/high resistance.
  11. Test for less then 1 ohm of resistance between the low reference circuit front end sensor connector and SDM connector.
  12. If greater than the specified range, test the circuit for an open/high resistance.
  13. If the circuits test normal, replace the appropriate front end sensor.
  14. Reconnect all SIR components. Ignition ON, with a scan tool clear and recheck for DTCs.
  15. If the front end sensor DTC returns and is current, replace the SDM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Inflatable Restraint Front End Sensor Replacement
    •  SIR/SRS Wiring Repairs
    •  Control Module References for SDM replacement, setup, and programming