GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2007 🢒 Allure 🢒 Driver Information and Entertainment 🢒 Displays and Gages 🢒 DTC B0935

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 B0935: Compass Sensor Circuit Open

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 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 compass connection failure occurs when the electronic compass module is disconnected or the sensor circuit(s) is open.

Conditions for Running the DTC

The instrument panel cluster (IPC) monitors the analog input value once every ignition cycle at power up.

Conditions for Setting the DTC

The IPC detects that the electronic compass module is not connected or the electronic compass sensor circuits are open.

Action Taken When the DTC Sets

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

Conditions for Clearing the DTC
    • The DTC will become history when a power cycle has been performed and the fault is not detected by the IPC.
    • A history DTC will clear after 100 fault-free ignition cycles.

Circuit/System Testing
  1. Ignition OFF, disconnect the harness connector at the electronic compass module.
  2. Ignition OFF, test for less than 1.0 ohm of resistance between the ground circuit terminal 14 and ground.
    3. ⇒If greater than the specified value, test the ground circuit terminal 14 for an open/high resistance.
  3. Ignition ON, verify that a test lamp illuminates when connected between the ignition 1 voltage circuit terminal 13 and the ground circuit terminal 14.
    4. ⇒If the test lamp does not illuminate, test the ignition 1 voltage circuit terminal 13 for a short to ground or an open/high resistance.
  4. Ignition OFF, disconnect the harness connector at the instrument panel cluster (IPC).
  5. Ignition OFF, test for less than 1 ohm of resistance between the compass sensor feed terminal 12 and 19.
    6. ⇒If greater than the specified value, test the compass sensor feed for an open/high resistance.
  6. Ignition OFF, test for less than 1 ohm of resistance between the compass sensor return terminal 11 and 18.
    7. ⇒If greater than the specified value, test the compass sensor feed for an open/high resistance.
  7. If all circuits test normal, test or 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