P2564

DTC P2564

DTC DESCRIPTORS

DTC P2564
Turbocharger Boost Control Position Sensor Circuit Low Voltage

DTC P2565
Turbocharger Boost Control Position Sensor Circuit High Voltage

DIAGNOSTIC FAULT INFORMATION






IMPORTANT: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

TYPICAL SCAN TOOL DATA

TC Vane Position Sensor:

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 and a turbocharger vane position sensor to control the turbocharger vanes. The ECM will vary the boost dependant upon the load requirements of the engine. 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.

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. Refer to Turbocharger Description and Operation.

CONDITIONS FOR RUNNING THE DTC

P2564
- The engine has been running for more than 3 seconds.
- DTC P2564 and P2565 run continuously when the above conditions are met.
- The ECM detects that the turbocharger vane position sensor signal voltage is less than 0.28 volts for more than one second.

P2565
- The engine has been running for more than 3 seconds.
- DTC P2564 and P2565 run continuously when the above conditions are met.
- The ECM detects that the turbocharger vane position sensor signal voltage is more than 4.8 volts for more than one second.

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
- Verify that any electrical aftermarket devices are properly connected and grounded. Refer to Checking Aftermarket Accessories.
- If the condition is intermittent, refer to Testing for Intermittent Conditions and Poor Connections and Inducing Intermittent Fault Conditions.

CIRCUIT/SYSTEM VERIFICATION

IMPORTANT: If you cannot duplicate the condition, 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.

1. If DTC P0698 or P0699 are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnostics.
2. With the engine running, observe the turbocharger (TC) vane position sensor and the desired TC vane position. Slowly increase the engine speed to 2,500 RPM, then return the engine speed to idle. The TC Vane Position Sensor parameter should remain very near or equal to the desired TC Vane Position parameter.
- If the parameter values do not follow each other, or stay near to or equal to the commanded position, continue with this diagnostic.

CIRCUIT/SYSTEM TESTING
1. With the TC vane position sensor disconnected, measure for a voltage of near 0 volts between the signal and the low reference circuits with a DMM.
- If the voltage is more than 4.7 volts, test the signal circuit for a short to voltage or a faulty ECM.
2. With the ignition and all electrical accessories OFF, allow sufficient time for the control module to power down before taking a resistance measurement. Measure for a resistance of less than 5 ohms with a DMM connected between the low reference circuit and a good ground.
- If the resistance is more than 5 ohms, test the low reference circuit for an open, high resistance, poor connection, or a faulty ECM.

IMPORTANT: The DMM and test leads must be calibrated to 0 ohms in order to prevent misdiagnosis. Use the DMM to perform this test. Refer to the DMM User Manual for calibration procedure.

3. With the ignition ON and the engine OFF, measure for a range of 4.8-5.2 volts between the 5-volt reference and the low reference circuits.
- If the voltage is less than 4.8 volts, test the 5-volt reference circuit for an open, high resistance, or a faulty ECM.
4. Connect a fused 3-amp jumper wire between the signal and the 5-volt reference circuit, observing the TC Vane Position Sensor parameter for a value of 100 percent.
- If the parameter does not increase to 100 percent, test the signal circuit for the following conditions:
- An open
- A short to ground
- High resistance
- A poor connection
- A faulty ECM
5. With the ignition OFF, remove the turbocharger vane position sensor. With a scan tool, observe the TC Vane Position parameter for a smooth decreasing value from 100-0 percent while slowly depressing the button on the end of sensor.
- If the parameter does not smoothly decrease, replace the turbocharger vane position sensor.
- If all circuits test OK, replace the faulty turbocharger vane position sensor.

REPAIR INSTRUCTIONS

IMPORTANT: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- Turbocharger Vane Position Sensor Replacement
- Control Module References for ECM replacement, setup, and programming