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 Descriptor

DTC B0931: Compass Sensor Circuit Malfunction

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Ignition 1 Voltage Circuit

--

B0935

--

B0931

Compass Sensor Feed

B0933

B0935

B0934

B0931

Compass Sensor Return

B0933

B0935

B0934

B0931

Compass Ground Circuit

--

B0935

--

B0931

Circuit/System Description

The internal fault detection of the electronic compass module is handled by the instrument panel cluster (IPC). The compass information is sent to the IPC via 2 discreet inputs from the electronic compass module. The IPC displays compass information in the driver information center (DIC). The DIC displays 2 dashes (- -) when the IPC looses connection with the electronic compass module.

Conditions for Running the DTC

The IPC monitors the analog input value at power up.

Conditions for Setting the DTC

When communication with the compass module exists but the IPC does not detect valid data from the electronic compass module or the compass error flag is set.

Action Taken When the DTC Sets

The DTC will be set and stored in non-volatile memory.

Conditions for Clearing the DTC

    • The DTC becomes history when the IPC no longer detects a failure.
    • The history DTC clears after 100 fault-free ignition cycles.

Reference Information

Schematic Reference

    •  Driver Information System Schematics
    •  Instrument Cluster Schematics

Connector End View Reference

Displays and Gages Connector End Views

Description and Operation

Driver Information Center (DIC) Description and Operation

Electrical Information Reference

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

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Data Definitions

Circuit/System Testing

  1. Verify that DTC B0931 is not set.
  2. If the DTC is set, calibrate the electronic compass module. If the DTC resets, replace the electronic compass module.
  3. Replace the electronic compass module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Electronic Compass Calibration
    •  Control Module References for the electronic compass module replacement, setup and programming