For 1990-2009 cars

### 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 activated, the body control module (BCM) detects a predetermined voltage signal. The BCM sends a serial data message to the engine control module (ECM) indicating the function that has been requested.

### Conditions for Running the DTC

The ignition is ON.

### Conditions for Setting the DTC

• | The ECM receives an invalid cruise control switch status serial data message from the BCM.

• | This diagnostic runs continuously.

### Actions Taken When the DTC Sets

• | The malfunction indicator lamp (MIL) will not illuminate.

• | The cruise control system is disabled.

### Conditions for Clearing the DTC

• | The condition responsible for setting the DTC no longer exists.

• | A history DTC will clear after 40 malfunction-free ignition cycles have occurred.

### Reference Information

#### Schematic Reference

Cruise Control Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Cruise Control 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 Verification

1. Verify that DTC B3794 is not set as current.

⇒ | If the DTC is set as current, refer to DTC B3794.

2. Road test the vehicle and attempt to engage cruise control. Verify that cruise control engages properly and that DTC P0575 does not set.

⇒ | If DTC P0575 sets as current, replace the BCM. Clear the DTC, road test the vehicle and attempt to engage cruise. If DTC P0575 resets as current, replace the ECM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM or ECM replacement, setup, and programming