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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2004 🢒 TopKick C-Series (Conventional) C4/C5 🢒 Engine 🢒 Engine Controls - 6.6L (LLY) 🢒 DTC P2563

Circuit Description

The position of the turbocharger vanes is controlled by the engine control module (ECM). The ECM utilizes a turbocharger vane control solenoid valve and a turbocharger vane position sensor to control the turbocharger vanes. When the engine is not under load, the turbocharger vanes are in an open position, or no boost condition. When the engine is under load, the ECM commands the control solenoid valve to close the turbocharger vanes, thus increasing the boost. The ECM will vary the boost dependant upon the load requirements of the engine. The vane position sensor uses the following 3 circuits:

    • A 5-volt reference circuit
    • A low reference circuit
    • A signal circuit

The ECM provides the sensor with 5 volts on the 5-volt reference circuit and a ground on the low reference circuit. Movement of the sensor from the closed position to the open position provides the ECM with a signal voltage through the position sensor signal circuit. If the ECM detects that the commanded position does not meet the actual position, DTC P2563 will set.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P2563 Turbocharger Vane Control Position Sensor Performance

Conditions for Running the DTC
    • The ignition is ON.
    • The ECM is not commanding the solenoid valve open or closed.

Conditions for Setting the DTC
    • The ECM detects that the commanded vane position does not match the actual position.
    • The above condition exists for more than 12 seconds.

Action Taken When the DTC Sets
    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC
    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Diagnostic Aids
    • If any service has been performed on the turbocharger or on the turbocharger components, a turbocharger relearn must be performed. Failure to perform the turbocharger learn procedure may cause this DTC to set. Refer to Turbocharger Learn .
    • An intermittent condition with the turbocharger vane control solenoid valve may cause this DTC to set. For an intermittent condition, refer to Intermittent Conditions .

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views

1

Did you perform the Diagnostic System Check - Engine Controls?

--

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2
  1. Turn ON the ignition, with the engine OFF.
  2. Monitor the DTC information with a scan tool.

Is DTC P0652, P0653, P2564, or P2565 also set?

--

Go to Diagnostic Trouble Code (DTC) List

Go to Step 3

3
  1. Perform the Turbocharger Learn Procedure. Refer to Turbocharger Learn .
  2. Turn OFF the ignition for 30 seconds.
  3. Turn ON the ignition, with the engine OFF.
  4. Clear the DTCs with the scan tool.

Is the procedure complete?

--

Go to Step 4

--

4
  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 5

Go to Diagnostic Aids

5
  1. Select the TC Vane Pos. Ctrl. Solenoid in Scan Tool Output Controls.
  2. Raise the engine RPM to 1,200 and maintain.
  3. Command the turbocharger vane position control solenoid valve ON with a scan tool.

Does the engine speed change when the valve is commanded ON?

--

Go to Step 6

Go to Step 9

6
  1. Select the TC Vane Position Sensor test in Scan Tool Output Controls.
  2. With the engine at idle, observe the TC Vane Position Sensor and the Desired TC Vane Position while commanding the TC Vane Position Sensor to 100 percent with the scan tool.

Is the TC Vane Position at or near the Desired TC Vane Position while commanding the TC Vane Position Sensor from 0 percent to 100 percent?

--

Go to Step 16

Go to Step 7

7
  1. Turn OFF the ignition.
  2. Disconnect the turbocharger vane position sensor.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure the voltage from the 5-volt reference circuit to a good ground with a DMM.

Is the voltage less than the specified value?

4.8 V

Go to Step 17

Go to Step 8

8

Measure the amperage between the 5-volt reference circuit and a good ground at the turbocharger vane position sensor connector with a DMM.

Is the amperage less than the specified value?

170 mA

Go to Step 18

Go to Step 14

9
  1. Turn OFF the ignition for 30 seconds.
  2. Disconnect the turbocharger vane control solenoid valve.
  3. Test for an intermittent and for a poor connection at the vane control solenoid valve. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 25

Go to Step 10

10
  1. Turn OFF the ignition.
  2. Disconnect the turbocharger vane position control solenoid valve.
  3. Measure the resistance of the turbocharger vane position control solenoid valve high control circuit with a DMM.

Is the resistance above the specified value?

5 ohms

Go to Step 19

Go to Step 11

11

Measure the resistance of the turbocharger vane position control solenoid valve low reference circuit with a DMM.

Is the resistance above the specified value?

5 ohms

Go to Step 19

Go to Step 12

12
  1. Remove the turbocharger vane position control solenoid valve . Refer to Turbocharger Control Solenoid Valve Replacement .

    2. Important: The solenoid valve may be in three different positions:

       • Open--Light is visible through the slot.
       • Closed--The surface of the valve in the slot is smooth.
       • At Rest--The surface of the valve in the slot is serrated.

  2. Observe both sets of slots on the side of the valve. A serrated surface, which is part of the sliding piece visible through the slots, should be fully visible in both slots.

Is the serrated surface visible through the solenoid valve slots?

--

Go to Step 13

Go to Step 22

13
  1. Connect the turbocharger vane position control solenoid valve connector.
  2. Turn ON the ignition, with the engine OFF.
  3. Depress and hold the button at the tip of the control solenoid valve.
  4. Command the control solenoid valve ON with the scan tool.
  5. Observe the slot closest to the button when commanding the solenoid valve to ON.

Does the spool valve move and open the slot on the vane control solenoid valve?

--

Go to Step 16

Go to Step 22

14
  1. Turn OFF the ignition for 30 seconds.
  2. Remove the turbocharger vane position sensor. Refer to Turbocharger Vane Position Sensor Replacement .
  3. Connect the turbocharger vane position sensor connector.
  4. Turn ON the ignition, with the engine OFF.
  5. Observe the TC Vane Position with the scan tool.

Is the TC Vane Position at the specified value?

100%

Go to Step 15

Go to Step 20

15
  1. Fully depress the turbocharger vane position sensor plunger.
  2. Observe the TC Vane Position with the scan tool.

Is the TC Vane Position at the specified value?

0%

Go to Step 16

Go to Step 20

16
  1. Inspect the turbocharger for debris or damage. Refer to Turbocharger Cleaning and Inspection in Engine Mechanical.
  2. If required, replace the turbocharger. Refer to Turbocharger Replacement .

Is the procedure complete?

--

Go to Step 25

--

17
  1. Turn OFF the ignition.
  2. Disconnect the engine control module (ECM).
  3. Test the vane position sensor 5-volt reference circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 25

Go to Step 21

18
  1. Turn OFF the ignition.
  2. Disconnect the engine control module (ECM).
  3. Test the vane position sensor 5-volt reference circuit for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 25

Go to Step 21

19

Repair the high resistance in the circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 25

--

20

Test for an intermittent and for a poor connection at the vane position sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 25

Go to Step 23

21

Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 25

Go to Step 24

22

Replace the turbocharger vane control solenoid valve. Refer to Turbocharger Control Solenoid Valve Replacement .

Did you complete the replacement?

--

Go to Step 25

--

23

Replace the turbocharger vane position sensor. Refer to Turbocharger Vane Position Sensor Replacement .

Did you complete the replacement?

--

Go to Step 25

--

24

Replace the ECM. Refer to Engine Control Module Replacement .

Did you complete the replacement?

--

Go to Step 25

--

25
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Perform the turbocharger learn procedure. Refer to Turbocharger Learn .
  5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 2

Go to Step 26

26

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List

System OK