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 C0750 03: Left Front Low Tire Pressure Sensor Low Voltage

DTC C0750 29: Left Front Low Tire Pressure Sensor Too Few Pulses

DTC C0750 39: Left Front Low Tire Pressure Sensor Internal Malfunction

DTC C0755 03: Right Front Low Tire Pressure Sensor Low Voltage

DTC C0755 29: Right Front Low Tire Pressure Sensor Too Few Pulses

DTC C0755 39: Right Front Low Tire Pressure Sensor Internal Malfunction

DTC C0760 03: Left Rear Low Tire Pressure Sensor Low Voltage

DTC C0760 29: Left Rear Low Tire Pressure Sensor Too Few Pulses

DTC C0760 39: Left Rear Low Tire Pressure Sensor Internal Malfunction

DTC C0765 03: Right Rear Low Tire Pressure Sensor Low Voltage

DTC C0765 29: Right Rear Low Tire Pressure Sensor Too Few Pulses

DTC C0765 39: Right Rear Low Tire Pressure Sensor Internal Malfunction

Circuit/System Description

The tire pressure monitor system has a radio frequency transmitting pressure sensor in each wheel/tire assembly. As vehicle speed increases, centrifugal force closes the sensors internal roll switch, which puts the sensor into rolling mode. The remote control door lock receiver receives and sends the data to the body control module (BCM). The BCM translates the data contained in the tire pressure sensor radio frequency transmissions into sensor presence, sensor mode, and tire pressure. Once vehicle speed is greater than 40 km/h (25 MPH), the remote function receiver module waits for the sensors to go into rolling mode. If one or more sensors do not go into rolling mode, or do not transmit at all, the BCM will set DTC C0750, C0755, C0760, or C0765 respectively.

Conditions for Running the DTC

Vehicle speed is greater than 40 km/h (25 MPH).

Conditions for Setting the DTC

    • A sensor does not transmit or transmits invalid data.
    • A sensor low battery condition.

Action Taken When the DTC Sets

    • The tire pressure monitor system indicator icon on the instrument cluster flashes for 1 min and then remains illuminated after the ignition switch is cycled ON and the instrument cluster bulb check is complete.
    • If equipped, the driver information center displays a service tire monitor type message.

Conditions for Clearing the DTC

A current DTC will clear when the malfunction is no longer present and 1 ignition cycle occurs.

Diagnostic Aids

    • Aftermarket wheel valve system locations can cause a sensor to not function correctly.
    • A sensor may have been damaged due to a previous wheel/tire service or flat tire event.
    • Occasionally sensor transmissions are not received by the remote function receiver module due to vehicle level radio frequency interference from items such as but not limited to aftermarket ignition systems, DVD players, CB radios, or metallic type window tinting.

Reference Information

Schematic Reference

Tire Pressure Monitoring System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Tire Pressure Monitor 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 diagnostic tester information

Circuit/System Verification

Using the scan tool, perform the BCM Tire Pressure Sensors Learn with the scan tool and cycle the ignition. Observe the scan tool tire pressures sensor pressure parameters. Verify the simulated tire pressures do not differ more than +/-30 kPa (3.6 psi) of the scan tool reading.

If not within the specified range, replace the concerned tire pressure sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Tire Pressure Indicator Sensor Replacement
    •  Tire Pressure Indicator Sensor Learn