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Engine Control System & Fuel System - 6.6l (Lmm) - DTC p2564 to DTC p2693 Chevrolet Chevy Express H1500

Testing & Diagnostics ~1591 words

Diagnostic Instructions

  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/chevy-express-h1500/2003-2012/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-system-check-vehicle) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/chevy-express-h1500/2003-2012/remont/oem-general-information/#vehicle-diagnostic-information__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/chevy-express-h1500/2003-2012/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-procedure-instructions) provide an overview of each diagnostic category.

Diagnostic Fault Information

CircuitShort to GroundHigh ResistanceOpenShort to VoltageSignal Performance
Turbocharger Vane Position Sensor 5-Volt ReferenceP0698, P2564P003A, P2563P2564P0699, P2565P2563
Turbocharger Vane Position Sensor Signal CircuitP2564P2563P2564P2565P2563
Turbocharger Vane Position Sensor Low Reference CircuitP003A, P2563P2565P2563

DTC P2564 or P2565

Typical Scan Tool Data

CircuitShort to GroundOpenShort to Voltage
Operating Conditions: Engine Running Parameter Normal Range: Varies, TC Vane Position Sensor Parameter Matches Desired TC Vane Position Parameter
5-Volt Reference Circuit0%100%
Turbocharger Vane Position Sensor Signal Circuit0%0%100%
Low Reference Circuit100%

TC Vane Position Sensor

Circuit/System Description

The position of the turbocharger vanes is controlled by the engine control module (ECM). The ECM commands the TC vane position solenoid to change the position of vanes in order to vary boost depending upon the load requirements of the engine. The TC vane position sensor provides the ECM with a signal voltage relative to position of the turbocharger vanes.

Conditions for Running the DTC

P2564

  1. The engine has been running for more than 3 seconds.
  2. DTC P2564 and P2565 run continuously when the above conditions are met.

P2565

  1. The engine has been running for more than 3 seconds.
  2. DTC P2564 and P2565 run continuously when the above conditions are met.

The ECM detects that the turbocharger vane position sensor voltage is less than 0.28 volt for greater than 1 second.

P2565

The ECM detects that the turbocharger vane position sensor signal voltage is greater than 4.7 volts for greater than 1 second.

Action Taken When the DTC Sets

DTCs P2464 and P2465 are Type B DTCs.

Conditions for Clearing the MIL/DTC

DTCs P2464 and P2465 are Type B DTCs.

Reference Information

Schematic Reference

Connector End View Reference

  1. «Engine Controls Connector End Views»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-2-of-2)
  2. «Engine Controls Component Views»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-2-of-2)
  3. «Engine Control Module Connector End Views»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-2-of-2)

Description and Operation Reference

  1. «Turbocharger System Description»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-2-of-2)
  2. «Turbocharger Learn»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lbz-and-lly-introduction-2-of-2__turbocharger-learn)

Electrical Information Reference

  1. «Circuit Testing»(/chevrolet/chevy-express-h1500/2003-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-troubleshooting-diagnosis__circuit-testing)
  2. «Connector Repairs»(/chevrolet/chevy-express-h1500/2003-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-troubleshooting-diagnosis__connector-repairs)
  3. «Testing for Intermittent Conditions and Poor Connections»(/chevrolet/chevy-express-h1500/2003-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-troubleshooting-diagnosis__testing-for-intermittent-conditions-and-poor)
  4. «Wiring Repairs»(/chevrolet/chevy-express-h1500/2003-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-troubleshooting-diagnosis__wiring-repairs)

DTC Type Reference

Scan Tool Reference

  1. «Scan Tool Data List (Engine Control Module)»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-1-of-2__scan-tool-data-list-engine-control) «Scan Tool Data List (Glow Plug Control Module)»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lbz-and-lly-introduction-1-of-2__scan-tool-data-list-glow-plug)
  2. «Scan Tool Data Definitions»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-1-of-2__scan-tool-data-definitions)
  3. «Scan Tool Output Controls»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-1-of-2__scan-tool-output-controls)

Circuit/System Verification

  1. Verify that DTCs P0698 or P0699 are not set. If any of the DTCs are set, refer to «DTC P0698 or P0699»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-dtc-p029d-to-dtc-p1448) .
  2. Engine running, observe the scan tool TC Vane Position Sensor and the Desired Vane Position parameters while slowly increasing the engine speed to 2,500 RPM, then returning the engine speed to idle. The TC Vane Position Sensor parameter should remain near or equal to the Desired Vane Position parameter.
  3. 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 Records data.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the TC vane position sensor.
  2. Ignition OFF for 90 seconds, test for less than 5 ohms of resistance between the low reference C and ground. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
  3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal D and ground. If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM. If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  4. Verify the scan tool TC Vane Position Sensor parameter is less than 2 percent. If greater than the specified range, test the signal circuit Terminal B for a short to voltage. If the circuit tests normal, replace the ECM.
  5. Install a 3A fused jumper wire between the signal circuit terminal B and the 5-volt reference circuit terminal D. Verify the scan tool TC Vane Position Sensor parameter is greater than 98 percent. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
  6. If all circuits test normal, test the TC vane position sensor.

Component Testing

IMPORTANTYou must perform the Circuit/System Testing in order to verify the integrity of the TC vane position sensor circuits before proceeding with Component Testing.

Erratic Signal Test

  1. Ignition OFF, disconnect the harness connector at the TC vane position sensor.
  2. Remove the TC vane position sensor.
  3. Connect the TC vane position sensor harness connector.
  4. Ignition ON, observe the scan tool TC Vane Position Sensor parameter while slowly depressing the button at the end of the sensor. There should be a smooth percentage change without any spikes or drop-outs.
  1. If the TC Vane Position parameter does not increment smoothly or is erratic, replace the TC vane position sensor.

Repair Procedures

  1. «Turbocharger Vane Position Sensor Replacement»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-2-of-2)
  2. «Control Module References»(/chevrolet/chevy-express-h1500/2003-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for ECM replacement, setup, and programming

Repair Verification

Engine running, observe the scan tool TC Vane Position Sensor and the Desired Vane Position parameters while slowly increasing the engine speed to 2,500 RPM, then returning the engine speed to idle. The TC Vane Position Sensor parameter should remain within 2 percent of the Desired Vane Position parameter.

  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/chevy-express-h1500/2003-2012/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-system-check-vehicle) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/chevy-express-h1500/2003-2012/remont/oem-general-information/#vehicle-diagnostic-information__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/chevy-express-h1500/2003-2012/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The control functions for the fuel injection system are integrated in the engine control module (ECM). During the manufacturing process, each injector's flow rate is measured and recorded as injection quantity adjustment (IQA) flow rate data. The flow rate data is then etched as a hexidecimal number on the body of the injector. This data, together with the injector's cylinder position, is stored in the memory of both the glow plug control module (GPCM) and the ECM. When the ignition is turned ON, both the GPCM and the ECM monitor to ensure that the fuel injection flow rate numbers are present. If any of the injector flow rate numbers are not programmed in the ECM this DTC will set.

The ignition is ON.

Conditions for Setting the DTC

The fuel injector IQA flow rate data is not programmed.

DTC P268A is a Type A DTC.

DTC P268A is a Type A DTC.

DTC Type Reference

Scan Tool Reference

  1. «Scan Tool Data List (Engine Control Module)»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-1-of-2__scan-tool-data-list-engine-control) «Scan Tool Data List (Glow Plug Control Module)»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lbz-and-lly-introduction-1-of-2__scan-tool-data-list-glow-plug)
  2. «Scan Tool Output Controls»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-1-of-2__scan-tool-output-controls)
  3. «Scan Tool Data Definitions»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-1-of-2__scan-tool-data-definitions)
  1. Review the Display ECM & GPCM Inj. Flow Rates parameter with a scan tool. All cylinders should be programmed with a flow rate number. Both the GPCM and the ECM should be programmed with the same flow rate numbers for the corresponding cylinders. If flow rate numbers are not present, refer to «Fuel Injector Flow Rate Programming»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-2-of-2) .
  2. Engine running, observe the DTC information with a scan tool. DTC P268A should not set.
  3. 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 Records data.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

  1. Perform the «Diagnostic System Check - Vehicle»(/chevrolet/chevy-express-h1500/2003-2012/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-system-check-vehicle) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(/chevrolet/chevy-express-h1500/2003-2012/remont/oem-general-information/#vehicle-diagnostic-information__strategy-based-diagnosis) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(/chevrolet/chevy-express-h1500/2003-2012/remont/oem-general-information/#vehicle-diagnostic-information__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The control functions for the fuel injection system are integrated in the engine control module (ECM). During the manufacturing process, each injector's flow rate is measured and recorded as injection quantity adjustment (IQA) flow rate data. The flow rate data is then etched as a hexadecimal number on the body of the injector. This data, together with the injector's cylinder position, is stored in the memory of both the glow plug control module (GPCM) and the ECM. When the ignition is turned ON, the GPCM and the ECM compare the IQA Data. If any of the injector flow rate numbers are incorrect in either of the control modules, this diagnostic will set the appropriate DTC.

The ignition is ON.

The fuel injector calibration flow rate data is incorrect.

DTCs P268C, P268D, P268E, P268F, P2690, P2691, P2692 and P2693 are Type A DTCs.

Conditions for Clearing the DTC

DTCs P268C, P268D, P268E, P268F, P2690, P2691, P2692 and P2693 are Type A DTCs.

DTC Type Reference

Scan Tool Reference

  1. «Scan Tool Data List (Engine Control Module)»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-1-of-2__scan-tool-data-list-engine-control) «Scan Tool Data List (Glow Plug Control Module)»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lbz-and-lly-introduction-1-of-2__scan-tool-data-list-glow-plug)
  2. «Scan Tool Output Controls»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-1-of-2__scan-tool-output-controls)
  3. «Scan Tool Data Definitions»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-1-of-2__scan-tool-data-definitions)
  1. Review the Display ECM & GPCM Inj. Flow Rates function with a scan tool. All cylinders should be programmed with a flow rate number. Both the GPCM and the ECM should be programmed with the same flow rate numbers for the corresponding cylinders. If flow rate numbers are incorrect, refer to «Fuel Injector Flow Rate Programming»(/chevrolet/chevy-express-h1500/2003-2012/remont/testing-diagnostics/#engine-control-system-fuel-system-66l-lmm-introduction-2-of-2) .
  2. Engine running, observe the DTC information with a scan tool. DTCs P268C, P268D, P268E, P268F, P2690, P2691 or P2693 should not set.
  3. 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 Records data.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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