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Home >> Cadillac >> 2005 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 16 (Cruise Control System) >> Diagnostic Information and Procedures >> DTC P0568 (6.6L): Cruise Control Set Switch Circuit >> Test Description
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Test Description

WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers on the diagnostic table.

  1. 2:  This step determines if condition is present.
DTC P0568 (6.6L)

Step Action Yes No
Schematic Reference : Cruise Control Schematics 
Connector End View Reference: Cruise Control Connector End Views  or Engine Control Module (ECM) Connector End Views in Engine Controls - 6.6L (LB7) or to Engine Control Module (ECM) Connector End Views in Engine Controls - 6.6L (LLY)
1 Did you perform the Cruise Control Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - Cruise Control 
2 
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Turn the cruise On/Off control switch ON.
  4. With the scan tool, observe the Cruise Set/Coast Switch parameter in the PCM Engine 1 Data, data list.
Does the Cruise Set/Coast Switch parameter display On?		 Go to Step 3  Go to Diagnostic Aids
3
  1. Turn OFF the ignition.
  2. Disconnect C1 of the ECM.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the cruise control set/coast switch signal circuit and a good ground.
Does the test lamp illuminate?		 Go to Step 4  Go to Step 6 
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 5 
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 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 Multifunction, Turn Signal Switch Replacement in Steering Wheel and Column.
Did you complete the replacement?		 Go to Step 9  -
8
IMPORTANT: Program the replacement ECM.
Replace the ECM. Refer to Engine Control Module (ECM) Replacement in Engine Controls-6.6L (LB7) or to Engine Control Module (ECM) Connector End Views in Engine Controls - 6.6L (LLY).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
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