P0568

DTC P0568

Circuit Description

The cruise control switch is an input to the instrument panel cluster (IPC). The IPC monitors the cruise control set/coast and resume/accelerate switch signal circuit in order to detect when a cruise control function has been requested. The IPC detects a specific voltage signal on the cruise control set/coast and resume/accelerate switch signal circuit when a cruise control function switch is activated, with each switch having a different predetermined voltage value. Once a cruise control function has been requested, the IPC sends a command via serial data to the engine control module (ECM).

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0568 Cruise Control Set Switch Circuit

Conditions for Setting the DTC

* The engine is running.
* Battery voltage is greater than 8 volts.
* The ECM detects the switch is switching too quickly or stuck for too long.

Action Taken When the DTC Sets

* The malfunction indicator lamp (MIL) will not illuminate.
* The ECM will record operating conditions at the time the diagnostic fail. This information will be stored in the Freeze Frame and Failure Records buffers.
* A history DTC is stored.
* The A/C compressor operation will be disabled while the low voltage indication exists.

Conditions for Clearing the MIL/DTC

* A history DTC will clear after 40 consecutive warm-up cycles without a fault.
* DTCs can be cleared by using the scan tool.
* Disconnecting the ECM battery feed for more than 10 seconds

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. This will help eliminate the possibility of an internally open or shorted contact coil.
* Ensure that the resume/accel switch is not stuck or sticking in the engaged position.

Test Description

The number below refers to the step number on the diagnostic table.
2. This step determines if condition is present.