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For 1990-2009 cars only

DTC P0568 2.2L


Object Number: 1243028  Size: MF

Circuit Description

The cruise control set/coast switch is an input to the engine control module (ECM). The ECM uses the cruise control set/coast switch signal circuit in order to detect when the driver has requested to set the vehicle speed or to decelerate the vehicle speed. The ECM detects a high signal voltage on the cruise control set/coast switch signal circuit when the switch is applied.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0568 Cruise Control Set Switch Circuit

Conditions for Running the DTC

    • The ignition is ON.
    • The cruise control On/Off switch is ON.

Conditions for Setting the DTC

The ECM detects a high signal voltage on the cruise control set/coast switch signal circuit for longer than 60 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 ECM records the operating conditions at the time the diagnostic fails. The ECM stores this information in the Failure Records.
    • The cruise control system is disabled.

Conditions for Clearing the MIL/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 MIL/DTC.

Diagnostic Aids

    • Ensure that the set/coast switch is not stuck in the engaged position.
    • For an intermittent condition, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Test Description

The number below refers to the step number on the diagnostic table.

  1. This step determines if condition is present.

Step

Action

Yes

No

Schematic Reference: Cruise Control Schematics

Connector End View Reference: Cruise Control Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Turn the cruise control On/Off switch ON.
  4. Observe the cruise set/coast parameter in the powertrain control module (PCM) General Info Inputs data list.

Does the cruise set/coast parameter display On?

Go to Step 3

Go to Diagnostic Aids

3

  1. Turn OFF the ignition.
  2. Disconnect the cruise control switch.
  3. Turn ON the ignition, with the engine OFF.
  4. Observe the cruise set/coast parameter.

Does the cruise set/coast parameter display On?

Go to Step 4

Go to Step 5

4

Test the cruise control set/coast switch signal circuit for a short to voltage. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

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 to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 7

6

Inspect for poor connections at the harness connector of the engine control module (ECM). Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

7

Replace the cruise control switch. Refer to Steering Wheel Control Switch Assembly Replacement in Steering Wheel and Column.

Did you complete the replacement?

Go to Step 9

--

8

Replace the ECM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 9

--

9

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC.

Does the DTC reset?

Go to Step 2

System OK

DTC P0568 3.5L


Object Number: 1402849  Size: MF

Circuit Description

The cruise control set/coast switch is an input to the powertrain control module (PCM). The PCM uses the cruise control set/coast switch signal circuit in order to detect when the driver has requested to set the vehicle speed or to decelerate the vehicle speed. The PCM detects a high signal voltage on the cruise control set/coast switch signal circuit when the switch is applied.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0568 Cruise Control Set Switch Circuit

Conditions for Running the DTC

    • The ignition is ON.
    • The cruise control On/Off switch is ON.

Conditions for Setting the DTC

The PCM detects a high signal voltage on the cruise control set/coast switch signal circuit for longer than 60 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.
    • The Service Vehicle Soon (SVS) light may be illuminated.

Conditions for Clearing the MIL/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 MIL/DTC.

Diagnostic Aids

    • Ensure that the set/coast switch is not stuck in the engaged position.
    • For an intermittent condition, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Test Description

The number below refers to the step number on the diagnostic table.

  1. This step determines if condition is present.

Step

Action

Yes

No

Schematic Reference: Cruise Control Schematics

Connector End View Reference: Cruise Control Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Turn the cruise control On/Off switch ON.
  4. Observe the cruise set/coast parameter in the powertrain control module (PCM) General Info Inputs data list.

Does the cruise set/coast parameter display On?

Go to Step 3

Go to Diagnostic Aids

3

  1. Turn OFF the ignition.
  2. Disconnect the cruise control switch.
  3. Turn ON the ignition, with the engine OFF.
  4. Observe the Cruise Set/Coast parameter.

Does the Cruise Set/Coast parameter display On?

Go to Step 4

Go to Step 5

4

Test the cruise control set/coast switch signal circuit for a short to voltage. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

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 to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 7

6

Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

7

Replace the cruise control switch. Refer to Steering Wheel Control Switch Assembly Replacement in Steering Wheel and Column.

Did you complete the replacement?

Go to Step 9

--

8

Replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 9

--

9

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC.

Does the DTC reset?

Go to Step 2

System OK