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 P0575: Cruise Control Switch Signal Circuit

Circuit/System Description

When a cruise control function switch is applied, the body control module (BCM) detects a predetermined voltage signal on the cruise control set/coast and resume/accelerate switch signal circuit. The BCM sends a GMLAN serial data message to the engine control module (ECM) indicating that the function has been requested.

Conditions for Setting the DTC

    • The ECM receives an invalid cruise control switch status GMLAN serial data message from the BCM.
    • This diagnostic runs continuously.

Action Taken When the DTC Sets

    • The Cruise Control System is disabled.
    • The ECM stores the DTC information into memory when this diagnostic runs and fails.
    • The malfunction indicator lamp (MIL) will not illuminate.
    • The ECM records the operating conditions at the time that this diagnostic fails. The ECM stores this information in the Failure Records.
    • All of the scan tool cruise control function switch parameters are set to Off.

Conditions for Clearing the DTC

    • A last test failed, or the current DTC, clears when the diagnostic runs and does not fail.
    • A history DTC clears after 40 consecutive warm-up cycles, if failures are not reported by this or any other emission related diagnostic.
    • Use the scan tool in order to clear the DTC.

Reference Information

Schematic Reference

Cruise Control Schematics

Connector End View Reference

Data Communication Connector End Views

Electrical Information Reference

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

Circuit/System Testing

Important: Fix any Cruise Control System related DTCs before using this diagnostic.

Important: This DTC may be stored as a history DTC without affecting the operation of the BCM. Do not replace the BCM if this DTC is stored only as a history DTC and is not retrieved as a current DTC.

Ignition ON, verify DTC P0575 is not current in the ECM.

If DTC P0575 is current, replace the BCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM replacement, setup, and programming