Buick Regal: DTC C056D

Diagnostic Instructions

• Perform the Diagnostic System Check prior to using this diagnostic procedure:Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis:Strategy Based Diagnosis
• An overview of each diagnostic category can be found here:Diagnostic Procedure Instructions

DTC Descriptor

DTC C056D

Electronic Control Unit Hardware

Symptom Byte Information: Symptom Byte List.

Circuit/System Description

The internal fault detection is handled inside the control module. No external circuit diagnosis is involved.

Conditions for Running the DTC

Ignition On

Conditions for Setting the DTC

K43 Power Steering Control Module = Malfunction

Actions Taken When the DTC Sets

K43 Power Steering Control Module = Disabled

Conditions for Clearing the DTC

• A current DTC will clear on the next malfunction-free ignition cycle.
• A history DTC will clear after 40 consecutive malfunction-free ignition cycles.

Diagnostic Aids

• This DTC can be set as a history DTC without affecting the operation of the component: K43 Power Steering Control Module
• If set only as a history DTC, do not replace any component.

Reference Information

Schematic Reference

Power Steering Wiring Schematics

Connector End View Reference

COMPONENT CONNECTOR END VIEW INDEX

Electrical Information Reference

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

Scan Tool Reference

Control Module References

Circuit/System Verification

1. Ignition - On / Vehicle - In Service Mode.

2. Verify DTC C056D is not set.

• If the DTC is set

1. Perform all necessary programming and setup procedures for the control module: K43 Power Steering Control Module
2. Verify the DTC does not set.
   • If the DTC sets - Replace the component: K43 Power Steering Control Module
   • Go to next step: If the DTC is not set
3. 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: Diagnostic Repair Verification

For control module replacement, programming, and setup refer to: Control Module References

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