GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P2563: Turbocharger Boost Control Position Sensor Performance

Diagnostic Fault Information

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

Turbocharger Vane Position Sensor 5-Volt Reference

P0107, P0698, P2564

P003A, P2563

P2564

P0106, P0699, P2565

P2563

Turbocharger Vane Position Sensor Signal Circuit

P2564

P003A, P2563

P2564

P2565

P2563

Turbocharger Vane Position Sensor Low Reference Circuit

--

P003A, P2563

P2565

--

P2563

Typical Scan Tool Data

TC Vane Position Sensor

Circuit

Short to Ground

Open

Short to Voltage

Parameter Normal Range: Varies, TC Vane Position Sensor parameter matches Desired TC Vane Position parameter

Turbocharger Vane Position Sensor 5-Volt Reference

0%

--

100%

Turbocharger Vane Position Sensor Signal

0%

0%

100%

Turbocharger Vane Position Sensor Low Reference Circuit

--

100%

--

Circuit/System Description

The position of the turbocharger vanes is controlled by the engine control module (ECM). The ECM utilizes a turbocharger vane control solenoid valve to control the turbocharger vanes, and a turbocharger vane position sensor to verify the position of the vanes. The ECM will vary the boost dependant upon the load requirements of the engine. Movement of the TC position sensor from the closed position to the open position provides the ECM with a signal voltage through the position sensor signal circuit.

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 TC vane position sensor with 5 volts on the 5-volt reference circuit and a ground on the low reference circuit.

Conditions for Running the DTC

    • DTCs P0045, P2564, or P2565 are not set.
    • The engine has been running for more than 30 seconds.
    • DTC P2563 run continuously when the above conditions are met.

Conditions for Running the DTC

The ECM detects that the difference between turbocharger vane position actual and desired is more than 15 percent for more than 5 seconds.

Action Taken When the DTC Sets

DTC P2563 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P2563 is a Type B DTC.

Diagnostic Aids

    • Verify that any electrical aftermarket devices are properly connected and grounded. Refer to Checking Aftermarket Accessories .
    • A MAP sensor that is skewed or bias may cause this DTC to set.
    • A restricted oil supply feed to the turbocharger may cause this DTC to set. Refer to Turbocharger Lack of Oil Supply .

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

    •  Engine Controls Connector End Views
    •  Engine Controls Component Views
    •  Engine Control Module Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Data Definitions
    •  Scan Tool Output Controls

Special Tools

J 34730-405 Injector Test Lamp

Circuit/System Verification

  1. If DTCs P003A, P0045, P0698, P0699, P2564, P2565 are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle for further information.
  2. Engine running, observe the TC Vane Position Sensor and the TC Desired Vane Position Sensor parameters. Command the TC vane position sensor in 5 percent increments, from 0-100  percent. The TC Vane Position Sensor and the Desired TC Vane Position parameters should remain equal to or near the commanded TC Vane Position.
  3. Engine running at idle speed, observe the scan tool TC Vane Position Sensor and the Desired TC Vane Position parameters while slowly increasing the engine speed to 2,500 RPM and slowly returning to idle speed.
  4. The TC Vane Position Sensor parameter should remain near or equal to the Desired TC Vane Position parameter throughout the engine speed range.
  5. Engine running, observe the DTC information with a scan tool. DTC P2563 should not set.
  6. 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 data.

Circuit/System Testing

Important: Perform the Circuit/System Verification before proceeding with the Circuit/System Testing.

  1. Ignition OFF, disconnect the harness connector of the TC vane position solenoid.
  2. Connect the J 34730-405 between the TC solenoid high control and low control circuits.
  3. Engine running, command the TC Pos. Cntrl. Solenoid ON and OFF with a scan tool. The test lamp should go from Bright to Dim.
  4. If the test lamp does not go from Bright to Dim with each command, test the TC solenoid high control and low control circuits for an open or short to ground. If the circuits test normal, test the low control and high control circuits for a short to voltage. If the circuits test normal, replace the ECM.
  5. Ignition OFF, disconnect the harness connectors at the TC vane position sensor, TC vane position solenoid, and the ECM.
  6. Ignition OFF, test for less than 5 ohms of resistance on all TC vane position sensor and TC vane position solenoid circuits between the following terminals:
  7. • ECM C1 low control circuit terminal 96 to TC solenoid terminal B
    • ECM C1 high control circuit terminal 48 to TC solenoid terminal A
    • ECM C1 5-volt reference circuit terminal 13 to TC sensor terminal D
    • ECM C1 low reference circuit terminal 63 to TC sensor terminal C
    • ECM C1 signal circuit terminal 20 to TC sensor terminal B
    If greater than 5 ohms, repair the affected circuit for an open/high resistance.
  8. Connect the ECM, the TC vane position sensor, and the TC vane position solenoid.
  9. If all the circuits test normal, test the TC vane position sensor and the TC vane position solenoid. Refer to Component Testing for instructions.
  10. Inspect the turbocharger for debris, sticking vanes, or damage. Refer to Turbocharger Cleaning and Inspection .
  11. If all circuits, the TC vane position sensor, and the TC vane position solenoid test normal, replace the turbocharger.

Component Testing

Important: Perform the Circuit/System Testing before proceeding with any of the Component Tests.

TC Control Solenoid

  1. Ignition OFF, disconnect the harness connector at the TC vane position solenoid.
  2. Test for a resistance of less than 7 ohms across the TC solenoid terminals.
  3. If greater than the specified range, replace the TC vane position solenoid.
  4. Ignition OFF, remove the TC vane position solenoid from the turbocharger.
  5. Connect the TC vane position solenoid harness connector.
  6. Ignition ON, command the TC Vane Pos. Cntrl. Solenoid ON. Depress and hold the CAM follower slightly at the tip of the TC solenoid valve while observing the slot closest to the CAM follower for the spool valve to move to the open position.
  7. If the spool valve did not move to the open position, replace the TC vane position solenoid.

TC Vane Position Sensor

  1. Remove the TC vane position sensor.
  2. Connect the TC vane position sensor harness connector.
  3. Ignition ON, observe the scan tool TC Vane Position Sensor parameter for a smooth percentage change while slowly depressing the button at the end of the TC vane position sensor. The percentage change should increment slowly without any spikes or dropouts.
  4. If the TC Vane Position parameter drops out or spikes, replace the TC vane position sensor.

Repair Instructions

Perform the Turbocharger Learn , then review the DTC information with a scan tool.

    •  Turbocharger Control Solenoid Valve Replacement
    •  Turbocharger Vane Position Sensor Replacement
    •  Turbocharger Removal
    •  Control Module References for ECM replacement, setup, and programming

Repair Verification

  1. Engine running, observe the TC Vane Position Sensor and the Desired TC Vane Position parameters. Slowly increase the engine speed to 2,500 RPM, and slowly return the engine speed to idle.
  2. The TC Vane Position Sensor parameter should remain near or equal to the desired TC Vane Position parameter.