P0568

DTC P0568 Cruise Set Switch Circuit Error




Circuit Description
The cruise control keeps the vehicle running at a fixed speed until a signal canceling this fixed speed is received. When the main switch is turned on with the vehicle is in the running mode, the battery voltage is applied to the powertrain control module (PCM). When a signal from the control switch is fed into the PCM while the vehicle is in this state, the cruise control system is activated. Also, while the PCM is operating, the "CRUISE MAIN" indicator lamp in the meter assembly lights up.
When the set switch is "ON", the vehicle speed is set.

Conditions for Setting the DTC
- The Ignition is "ON".
- Engine is running.
- System voltage is between 11.5 volts - 16 volts.
- The switch contact remains on for 120 seconds or more.
- Noises are generated by the poor switch contact 100 times within 1.6 seconds.

Action Taken When the DTC Sets
- The PCM will not illuminate the Malfunction Indicator Lamp (MIL).
- The PCM will store conditions, which were present when the DTC was set in the Failure Records data only.

Conditions for Clearing the MIL/DTC
- The PCM will turn the MIL "OFF" on the third consecutive trip cycle during which the diagnostic has been run and the fault condition is no longer present.
- A history DTC P0568 will clear after 40 consecutive trip cycles during which the warm up cycles have occurred without a fault.
- DTC P0568 can be cleared using the Tech 2 "Clear Info" function or by disconnecting the PCM battery feed.

Steps 1 - 8:

Diagnostic Aids
An Intermittent may be caused by the following:
- Poor connections.
- Mis routed harness.
- Rubbed through wire insulation.
- Broken wire inside the insulation.

Check for the following conditions:
- Poor connection at PCM - Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection.
- Damaged harness - inspect the wiring harness for damage. If the harness appears to be okay, observe the cruise main switch display on the Tech 2 while moving the connectors and wiring harnesses related to the sensor. A change in the display will indicate the location of the fault.

If DTC P0568 cannot be duplicated, the information included in the Failure Records data can be useful in determining vehicle mileage since the DTC was last set.

If it is determined that the DTC occurs intermittently, performing the DTC P0568 Diagnostic Chart may isolate the cause of the fault.