Diagnostic Instructions

DTC Descriptors

DTC P0047: Turbocharger Boost Control Solenoid Control Circuit Low Voltage

DTC P0048: Turbocharger Boost Control Solenoid Control Circuit High Voltage

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Turbocharger Vane Position Control Solenoid Valve High Control	P003A, P0047, P0401	P003A, P0047, P0401	--	P003A, P0401
Turbocharger Vane Position Reference Solenoid Valve Low Control	P003A, P0047, P0401	P003A, P0047, P0401	P003A, P0048	P003A, P0401

Circuit/System Description

The positions of the turbocharger vanes are controlled by the engine control module (ECM). The ECM utilizes a turbocharger vane control solenoid to control the turbocharger vanes and a turbocharger vane position sensor to verify the vanes position. The ECM will vary the boost dependant upon the load requirements of the engine. The vane control solenoid has a high control circuit and a low control circuit. The ECM uses a pulse width modulation on both circuits to control the solenoid.

Conditions for Running the DTC

Conditions for Setting the DTC

Action Taken When the DTC Sets

DTCs P0047 and P0048 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0047 and P0048 are Type B DTCs.

Diagnostic Aids

If there is a loss of ignition voltage to the ECM terminal C1-76 this DTC may set. Verify this circuit is not shorted to ground or open. Verify the supply fuse for this circuit is not open.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

J 34730-405 Injector Test Lamp

Circuit/System Verification

1. Verify that DTCs P0652, P0653, P0698, P0699, P2564, or P2565 are not set.

⇒	If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle.

2. Engine running, increase the engine speed to 1,500 RPM and maintain. Command the TC Vane Pos. Ctrl. Solenoid ON and OFF with a scan tool while observing the Vane Position Sensor parameter. The TC Vane Position Sensor parameter should increase to 95-97 percent and decrease to near 0 percent when changing between the commanded states.
3. Engine running, observe the TC Vane Position Sensor and the Desired TC Vane Position parameters with a scan tool. Slowly increase the engine speed from idle to 2,500 RPM, and slowly return the engine to idle speed. The TC Vane Position Sensor parameter should remain near or equal to the Desired TC Vane Position parameter throughout the engine speed range.
4. Engine running, observe the TC Vane Position Sensor and the Desired TC Vane Position parameters while increasing the TC vane position in 5 percent increments from 0-100 percent with a scan tool. The parameters should remain within 2 percent of each other during the entire range.
5. Operate the vehicle within the Conditions for Running the DTC to verify that 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 TC vane control solenoid.

Important: When the engine coolant temperature is less than 70°C (158°F), the test lamp will change brightness when commanded with a scan tool. When the ECM is attempting a TC Learn, the test lamp will flash ON and OFF without commands from a scan tool.

2. Connect the J 34730-405 between the high control circuit terminal A and the low control circuit terminal B.
3. Engine running, engine coolant temperature (ECT) sensor 1 must be less than 70°C (158°F). Command the TC Vane Pos. Ctrl. Solenoid ON and OFF with a scan tool. The test lamp should illuminate and change from bright to dim when changing between the commanded states.

⇒	If the test lamp does not illuminate, test the low control circuit terminal B for an open/high resistance or a short to voltage. If the circuit tests normal, test the high control circuit terminal A for a short to ground or an open/high resistance. If the circuits test normal, replace the ECM.

⇒	If the test lamp remains illuminated, test the low control circuit terminal B for a short to ground.

4. Ignition OFF, test for a resistance between 2-7 ohms across the terminals of the TC vane control solenoid.

⇒	If the resistance is not within the specified range, replace the TC vane position solenoid.

5. Test for infinite resistance between each terminal and the TC vane control solenoid housing.

⇒	If less than infinite resistance, replace the TC vane control solenoid.

6. If all circuits test normal, replace the TC control vane control solenoid.

Repair Instructions

Repair Verification

1. Install any components or connectors that have been removed or replaced during diagnosis.
2. Perform any adjustment, programming, or setup procedures that are required when a component or module is removed or replaced.
3. Clear the DTCs.
4. Turn OFF the ignition for 90 seconds.
5. Duplicate the Conditions for Running the DTC and use the freeze Frame/Failure Records, if applicable, in order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to the Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.
6. If any service has been performed on the turbocharger or on the turbocharger components, a turbocharger relearn must be performed. Failure to perform the turbocharger learn procedure may cause this DTC to set. Refer to Turbocharger Learn.