Circuit Description
The cruise control switch is an input to the powertrain control module (PCM). The PCM 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 PCM 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.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0564 Cruise Control Multi-Function Switch Circuit
Conditions for Running the DTC
| • | The ignition is ON. |
| • | The cruise control on/off switch is ON. |
Conditions for Setting the DTC
This DTC sets when the PCM detects an invalid voltage signal on the cruise control set/coast and resume/accelerate switch signal circuit for greater than 1.5 seconds.
The PCM runs this diagnostic every 0.05 seconds.
Action Taken When the DTC Sets
| • | The PCM stores the DTC information into memory when the diagnostic runs and fails. |
| • | The malfunction indicator lamp (MIL) will not illuminate. |
| • | The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records. |
| • | The Cruise Control System is disabled. |
Conditions for Clearing the DTC
| • | A last test failed, or the current DTC, clears when the diagnostic runs and does not fail. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if failures are not reported by this or any other emission related diagnostic. |
| • | Use a scan tool in order to clear the DTC. |
Diagnostic Aids
For an intermittent condition, refer to Testing for Intermittent Conditions and Poor Connections .
Step | Action | Values | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Cruise Control Schematics Connector End View Reference: Master Electrical Component List | ||||||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |||||||
2 |
Does the voltage measure at the specified value? | B+ | Go to Step 3 | Go to Step 7 | ||||||
3 |
Important: The cruise control on/off switch must be turned ON in order to correctly view the set/coast switch resistance value with the DMM.
Does the cruise control function switch resistance values measure within the specified values? | Off = O.L. On = 7.8 K ohms - 8.6 K ohms Resume = 2.7 K ohms - 3.0 K ohms Set = 1.2 K ohms - 1.3 K ohms | Go to Step 4 | Go to Step 5 | ||||||
4 | Test the cruise control set/coast and resume/accelerate switch signal circuit between the cruise control switch and the powertrain control module (PCM) for the following:
Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 6 | ||||||
5 | Inspect for poor connections at the harness connector of the cruise control switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 8 | ||||||
6 | Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 9 | ||||||
7 | Repair the high resistance in the ignition 1 voltage circuit. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair? | -- | Go to Step 10 | -- | ||||||
8 | Replace the cruise control switch. Refer to Turn Signal Multifunction Switch Replacement . Did you complete the replacement? | -- | Go to Step 10 | -- | ||||||
9 | Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 10 | -- | ||||||
10 |
Does the DTC reset? | -- | Go to Step 2 | System OK | ||||||
