P0568

DTC P0568

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0568 00
- Cruise Control Set Switch Circuit

Circuit/System Description

The cruise control resume/accel switch is an input to the engine control module (ECM) / powertrain control module. The ECM (5.3L) / PCM (3.8L) uses the cruise control resume/accel switch signal circuit in order to detect when the driver has requested to accelerate the set vehicle speed or to resume the cruise control system. The ECM/PCM detects a voltage signal on the cruise control resume/accel switch signal circuit when the switch is applied.

Conditions for Running the DTC

* The ignition is ON.
* The cruise control switch is ON.

Conditions for Setting the DTC

The ECM detects that the set/coast switch is applied for longer than 60 seconds.

Action Taken When the DTC Sets

* The ECM/PCM stores the DTC information into memory when the diagnostic runs and fails.
* The malfunction indicator lamp (MIL) will not illuminate.
* The ECM/PCM records the operating conditions at the time the diagnostic fails. The ECM/PCM stores this information in the Failure Records.
* The cruise control system is disabled.

Conditions for Clearing the DTC

* The DTC becomes history when the conditions for setting the DTC are no longer present.
* The history DTC clears after 40 malfunction-free warm-up cycles.
* The ECM receives a clear code command from the scan tool.

Diagnostic Aids

Perform the following in order to avoid misdiagnosis:

* Rotate the steering wheel to both steering stops and activate each cruise control switch separately. With a scan tool, observe the associated cruise control switch parameter in the ECM/PCM Cruise Control data list. This will help eliminate the possibility of an internally open or shorted inflatable restraint steering wheel module coil.
* Ensure that the resume/accel switch is not stuck or sticking in the engaged position.
* For an intermittent condition, Refer to Testing for Intermittent Conditions and Poor Connections in Diagnostic Aids. Component Tests and General Diagnostics

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the cruise control switch.
2. Ignition ON, cruise control switch ON, observe the scan tool Cruise Set/Coast Switch parameter.

• If the scan tool parameter reads Inactive or Off, replace the cruise control switch assembly.
• If the scan tool parameter reads On, Active or Invalid, test the cruise control switch signal circuit for a short to voltage. If the circuit tests normal, replace the ECM/PCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* Turn Signal Multifunction Switch Replacement
* Programming and RelearningProgramming and Relearning