Buick Regal: DTC C0774

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 C0774 00

Tire Pressure Monitoring System

Circuit Description

The electronic brake control module (EBCM) receives a serial data message from the tire pressure monitor (TPM) system when low tire pressure is detected. The EBCM will adjust the responses of vehicle stability enhancement system (VSES) to have optimal vehicle control when active.

Conditions for Running the DTC

• Engine is running.
• Battery voltage is between 9 - 16 V.
• Vehicle speed is greater than 3.6 km/h (2.2 mph).
• DTC runs continuously once the above conditions are met.

Conditions for Setting the DTC

• The tire pressure in any of the tires is below 104 kPa (15.1 psi).
• The compact spare tire is present on the rear axle.

Actions Taken When the DTC Sets

• The ESC will become permanently active.
• No warning indicators and/or messages will be displayed.

Conditions for Clearing the DTC

• The condition for the DTC is no longer present.
• All tires have correct pressures.

Reference Information

Description and Operation

Tire Pressure Monitor Description and Operation

Scan Tool Reference

Control Module References for scan tool information.

Circuit/System Verification

1. Verify there are no TPM DTCs DTC C0750, C0755, C0760, and C0765 set along with DTC C0774.

• If DTC is set

Refer to DTC C0750, C0755, C0760, or C0765.

• If DTC is not set

Verify tire pressure. Refer to Symptoms - Tire Pressure Monitoring.

DTC C0775

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 C0775 00

Tire Pressure Monitoring System Sensors Malfunction

Circuit/System Description

If the body control module (BCM) has been reprogrammed or replaced and the tire pressure sensor learn procedure has not been performed, the tire pressure monitor system indicator icon on the instrument cluster will flash for 1 min and then remain illuminated after the power switch is cycled ON and the instrument cluster bulb check is complete.

If equipped, the driver information center will also display a service tire monitor type message. Under these circumstances, DTC C0775 will be set in the BCM and the tire pressure sensor learn procedure will need to be performed for the system to function correctly.

Conditions for Running the DTC

Vehicle ON or Vehicle in Service Mode.

Conditions for Setting the DTC

The body control module (BCM) has not learned tire pressure sensor ID and location information from the tire pressure sensors.

Action Taken When the DTC Sets

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

Conditions for Clearing the DTC

A current DTC will clear when the BCM has received tire pressure sensor ID and location after tire pressure sensor indicator learn procedure has been performed.

Reference Information

Description and Operation

Tire Pressure Monitor Description and Operation

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Perform the Tire Pressure Indicator Sensor Learn.

2. Verify DTC C0775 is not set.

• If the DTC is set

1. Test the keyless entry antenna for proper operation. Refer to Keyless Entry System Malfunction (Active) Keyless Entry System Malfunction (Passive).
2. Clear DTC.
3. Verify DTC does not set.
   • If the DTC sets, replace the K9 Body Control Module.
   • Go to next step: If the DTC does not set.
   • Go to next step: All OK.

Go to next step: If the DTC is not set

3. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for control module replacement, programming, and setup.

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