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P0564



DTC P0564

DTC Descriptor

DTC P0564 00
- Cruise Control MultiFunction Switch Circuit

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview






Circuit/System Description

The cruise control switch is an input to the engine control module (ECM), while the cruise cancel switch is an input to the body control module (BCM). The ECM monitors the cruise control on/off, set/coast, and the resume/accelerate switch signal circuits in order to detect when a cruise control function switch has been activated. The ECM detects a predetermined voltage signal when a cruise control function switch is applied, with each switch having a different voltage value.

The BCM monitors the cruise cancel switch in order to detect when the cancel switch has been activated. The BCM sends a class 2 message to the ECM regarding the status of the cruise cancel switch.

Conditions for Running the DTC

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

Conditions for Setting the DTC

* The ECM detects an invalid voltage signal on the cruise control set/coast and resume/accelerate switch signal circuit.
* The above condition is present for greater than 1.5 seconds.
* The PCM/ECM runs this diagnostic every 0.05 seconds.

Action Taken When the DTC Sets

* The ECM stores the DTC information into memory when the diagnostic runs and fails.
* The malfunction indicator lamp (MIL) will not illuminate.
* The Cruise Control System is disabled.

Conditions for Clearing the DTC

* The DTC becomes history when the fault is no longer present.
* A History DTC clears after 100 malfunction-free ignition cycles.
* The ECM receives a clear code command from the scan tool.

Diagnostic Aids

* With a scan tool, observe the cruise control function switch parameters, in the Cruise Control ECM data list, while rotating the steering wheel to both steering stops and individually activating each cruise control function switch separately. This will help eliminate the possibility of an internally shorted inflatable restraint steering wheel module coil.
* For an intermittent condition, refer to Testing for Intermittent Conditions and Poor Connections in Diagnostic Aids. Component Tests and General Diagnostics

Circuit/System Testing

Caution: Refer to Restraint System Service Precautions.

Disable the inflatable restraint steering wheel module when performing this diagnostic. Refer to SIR Disabling and Enabling.

1. Ignition OFF, remove the inflatable restraint steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement.
2. Disconnect the harness connector of the cruise control switch assembly.
3. Ignition ON, measure for 10 volts or greater at the cruise control supply voltage circuit.

If less than the specified value, check for an open/high resistance or a short to ground on the cruise control supply voltage circuit.

4. Ignition ON, verify that a test lamp illuminates between B+ the cruise control switch signal circuit.

If the test lamp does not illuminate, test the cruise control switch signal circuit for an open/high resistance or a short to voltage. If the circuit tests normal, replace the ECM.

5. Ignition OFF, test the cruise control switch signal circuit for a short to ground.

If the circuit tests normal, test the component. If the circuits and the component tests are normal, replace the ECM.

Component Testing

Caution: Refer to Restraint System Service Precautions.

Disable the inflatable restraint steering wheel module when performing this diagnostic. Refer to SIR Disabling and Enabling.

Important: The cruise control switch must be ON in order to properly measure the resistance of the - SET, the + RES, and the Cancel switches.

1. Ignition OFF, remove the inflatable restraint steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement.
2. Disconnect the harness connector at the cruise control switch.
3. Cruise control switch ON, measure the resistance between terminals 2 and 1 at the cruise control switch side of the connector. Individually activate and hold each cruise control function switch and compare the resistance reading to the values on the schematic for the ON/OFF, - SET, and the + RES.

If any of the resistance measurements for the OFF, ON, - SET, and + RES are not within the listed resistance values, replace the cruise control switch assembly.

4. Cruise control switch ON, measure the resistance between terminals 2 and 3 at the cruise control switch side of the connector. Activate and deactivate the cancel switch.

If the resistance does not show continuity when activated and open when deactivated, replace the cruise control switch assembly.






Repair Instructions

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

* Cruise Control Switch Replacement
* Programming and Relearning for ECM setup, and programming. Programming and Relearning