DTC B0933. Buick Allure 2009

For 1990-2009 cars only

Makes 🢒 Buick 🢒 2009 🢒 Allure 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC B0933

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 B0933: Compass Sensor Circuit Low

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Ignition 1 Voltage	--	B0935	--	B0931
Compass Sensor Feed	B0933	B0935	B0934	B0931
Compass Sensor Return	B0933	B0935	B0934	B0931
Compass Ground	--	B0935	--	B0931

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 wire inputs from the electronic compass module. The IPC displays compass information in the driver information center (DIC).

Conditions for Running the DTC

The instrument panel cluster (IPC) monitors the analog input values at power up.

Conditions for Setting the DTC

The IPC detects that either compass input circuit(s) is shorted to ground.

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.

•	The history DTC clears after 100 fault-free ignition cycles.

Reference Information

Schematic Reference

•	Instrument Cluster Schematics

•	Driver Information System Schematics

Connector End View Reference

Component 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

Control Module References for scan tool information

Circuit/System Testing

Ignition OFF, disconnect the harness connector at the electronic compass module.
Ignition OFF, test for less than 1 ohm between the ground circuit terminal 14 and ground.

⇒	If greater than the specified value, test the ground circuit for an open/high resistance.

Ignition ON, verify that a test lamp illuminates when connected between the ignition voltage circuit terminal 13 and the ground circuit terminal 14.

⇒	If the test lamp does not illuminate, test the ignition voltage circuit for a short to ground or an open/high resistance.

Ignition ON, verify a test lamp does not illuminate when connected between the compass sensor feed terminal 12 and the ignition voltage circuit terminal 13.

⇒	If the test lamp illuminates, test the compass sensor feed terminal 12 for a short to ground.

Ignition ON, verify a test lamp does not illuminate when connected between the compass sensor return terminal 11 and the ignition voltage circuit terminal 13.

⇒	If the test lamp illuminates, test the compass sensor return terminal 11 for a short to ground.

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