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P0245




DTC P0243, P0245, or P0246

Diagnostic Instructions

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

DTC Descriptors
DTC P0243
- Turbocharger Wastegate Solenoid Valve Control Circuit

DTC P0245
- Turbocharger Wastegate Solenoid Valve Control Circuit Low Voltage

DTC P0246
- Turbocharger Wastegate Solenoid Valve Control Circuit High Voltage

Diagnostic Fault Information





Circuit/System Description

The Borg-Warner(TM) dual-scroll turbocharger incorporates a wastegate that is controlled by the ECM, by means of a PWM solenoid, to regulate the pressure ratio of the compressor. An integral turbocharger bypass valve, controlled by the ECM through a remotely mounted solenoid, is used to prevent compressor surging and damage by opening during abrupt closed throttle conditions. The bypass valve opens during closed throttle deceleration conditions, which allows the air to recirculate in the turbocharger and maintain compressor speed. During a wide open throttle command, the bypass valve closes to optimize turbo response.

At idle the turbocharger wastegate solenoid is commanded to 0 % by the ECM. When the engine load and RPM increases under a wide open throttle, the wastegate solenoid is briefly commanded to as great as 90-100 %. When the proper level of boost pressure is attained, the ECM decreases the PWM of the solenoid to a range of 65-85 %. As soon as the throttle closes the ECM commands the solenoid back to 0 %, to allow the wastegate to open, which reduces the speed of the turbine.

Conditions for Running the DTCs

* The ignition is ON.
* The battery voltage is between 11-32 V.
* The DTCs run continuously when the above conditions have been met.

Conditions for Setting the DTCs

The ECM detects an open, a short to ground, or a short to voltage on the turbocharger wastegate solenoid control circuit for greater than 2 s.

Action Taken When the DTCs Set

* DTCs P0243, P0245, P0246 are Type B DTCs.
* The ECM will disable boost control and limit the system to mechanical boost only, resulting in a substantial decrease in engine power.

Conditions for Clearing the MIL/DTCs

DTCs P0243, P0245, P0246 are Type B DTCs.

Reference Information
Schematic Reference

Engine Controls Schematics ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

Turbocharger System Description (Description and Operation)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)
Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

* Perform an inspection of the turbocharger. Refer to Turbocharger Cleaning and Inspection (LDK, LHU) (43. Turbocharger Cleaning and Inspection).
* Command the Turbocharger Wastegate Solenoid parameter from 0-100 % with a scan tool. A series of clicks should be heard and felt when commanded between 20-90 %.
* 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, disconnect the harness connector at the Q42 turbocharger wastegate solenoid valve.
2. Ignition ON, verify that a test lamp illuminates between the voltage supply circuit terminal 1 or A and ground.

• If a test lamp does not illuminate test the voltage supply circuit for a short to ground or an open/high resistance.

3. Verify that a test lamp does not illuminate between the control circuit terminal 2 or B and ground.

• If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.

4. Connect a test lamp between the control circuit terminal 2 or B and the voltage supply circuit terminal 1 or A.
5. Command the Turbocharger Wastegate Solenoid parameter to 50 % with a scan tool. The test lamp should illuminate and flash rapidly when commanded to 50 % and turn OFF when commanded to 0 %.

• If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K20 ECM.
• If the test lamp is always OFF, test the control circuit for an open/high resistance. If the circuit tests normal, replace the K20 ECM.

6. If the circuits test normal, test or replace the Q42 turbocharger wastegate solenoid valve.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Turbocharger Wastegate Regulator Solenoid Valve Replacement (Turbocharger Wastegate Regulator Solenoid Valve Replacement)
* Control Module References (Programming and Relearning) for ECM replacement, setup and programming

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