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 Descriptors

DTC P0045 01: Turbocharger Boost Control Solenoid Control Circuit Short to Battery

DTC P0045 02: Turbocharger Boost Control Solenoid Control Circuit Short to Ground

DTC P0045 04: Turbocharger Boost Control Solenoid Control Circuit Open

DTC P0045 54: Turbocharger Boost Control Solenoid Control Circuit Temperature High

Circuit/System Description

The position of the turbocharger vanes is controlled by the engine control module (ECM). The ECM utilizes a turbocharger vane position control solenoid or a boost pressure actuator and a turbocharger pressure sensor to control the turbocharger vanes. The ECM will vary the boost dependant upon the load requirements of the engine. The ECM uses a pulse width modulation on the control circuit to control the solenoid valve.

Conditions for Running the DTC

    • The ignition is ON or the engine is running.
    • The ignition voltage is greater than 16.5  volts.
    •  The ECM has commanded the turbocharger boost control solenoid ON and OFF at least once during the ignition cycle.
    • The DTCs run continuously once the above conditions are met.

Conditions for Setting the DTC

P0045 01, P0045 02, and P0045 04

The control module detects that the commanded state of the driver and the actual state of the control circuit do not match.

P0045 54

The control module detects that the output driver chip temperature is too high.

Action Taken When the DTC Sets

DTC P0045 is a Type B DTC.

Conditions for Clearing the DTC

DTC P0045 is a Type B DTC.

Diagnostic Aids

Engine running, increase the engine speed to 1,500 RPM and maintain. With a scan tool, command the Turbocharger Vane Position Solenoid Valve ON and OFF. The Turbocharger Vane Position Solenoid Valve Command parameter should increase to 95-97 percent when the Turbocharger vane position solenoid is commanded ON and decrease to near 0 percent when commanded OFF.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

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

Description and Operation

Turbocharger System Description

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Ignition ON, command the turbocharger vane position solenoid valve between 0-5 percent with a scan tool. You should hear an audible click.
  2. Engine running, command the turbocharger vane position solenoid valve between 0-5 percent with a scan tool. You should hear an audible click.
  3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

  1. Ignition OFF and the MAIN fuse removed, disconnect the harness connector at the turbocharger boost control solenoid.
  2. Test for less than 5 Ω between the ground circuit terminal 2 and ground.
  3. If greater than the specified range, repair the open/high resistance in the ground circuit.
  4. Install the MAIN fuse. Ignition ON, verify that a test lamp illuminates between the ignition voltage circuit terminal 1 and ground.
  5. If the test lamp does not illuminate, test the ignition voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition voltage circuit fuse is open, test all components connected to the ignition 1 voltage circuit and replace as necessary.
  6. Test for 3-4 V between the control circuit terminal 4 and ground.
  7. If less than the specified range, test the control circuit for an open or a short to ground. If the circuit tests normal, replace the K20 ECM.
    If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.
  8. Connect a test lamp between the control circuit terminal 4 and the ignition voltage circuit terminal 1.
  9. Clear the DTC information parameter with a scan tool. Command the turbocharger vane position solenoid valve between 5-95 percent with a scan tool. The test lamp should illuminate brightly at 5 percent, and decrease up to 95 percent.
  10. If the test lamp does not respond to the scan tool commands replace the K20 ECM.
  11. If all circuits test normal, test or replace the turbocharger.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Turbocharger Replacement
    •  Control Module References for engine control module replacement, setup, and programming