Diagnostic Instructions

DTC Descriptors

DTC P0033 : Turbocharger Bypass Solenoid Valve Control Circuit

DTC P0034: Turbocharger Bypass Solenoid Valve Control Circuit Low Voltage

DTC P0035: Turbocharger Bypass Solenoid Valve Control Circuit High Voltage

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Ignition Voltage	P0033, P0034	P0033	--	--
Turbocharger Bypass Solenoid Valve Control Circuit	P0034	P0033	P0035	--

Circuit/System Description

The turbocharger bypass solenoid valve is used to prevent the compressor from exceeding the pump limit at low compressor flow and high pressure. This occurs when the engine is running with a load and the throttle suddenly closes. In this case, flow is almost null and pressure is very high. This not only is damaging to the turbocharger, but also generates noise and decelerates turbine speed. The bypass solenoid valve is pulse width modulated (PWM). Ignition voltage is supplied directly to the bypass solenoid valve. The engine control module (ECM) controls the solenoid valve by grounding the control circuit with a solid state device called a driver. The driver is equipped with a feedback circuit that is pulled-up to a voltage. The ECM can determine if the control circuit is open, shorted to ground, or shorted to a voltage by monitoring the feedback voltage.

Conditions for Running the DTC

Conditions for Setting the DTC

P0033

The ECM detects the bypass solenoid valve control circuit is open. The condition exists for 4 seconds or a cumulative of 30 seconds.

P0034

The ECM detects the bypass solenoid valve control circuit is shorted to ground. The condition exists for 4 seconds or a cumulative of 30 seconds.

P0035

The ECM detects the bypass solenoid valve control circuit is shorted to voltage. The condition exists for 4 seconds or a cumulative of 30 seconds.

Action Taken When the DTC Sets

DTC P0033, P0034, and P0035 are Type B DTCs.

Conditions for Clearing the DTC

DTC P0033, P0034, and P0035 are Type B DTCs.

Diagnostic Aids

If the condition is intermittent, move the related harnesses and connectors, with the engine operating, while monitoring the circuit status for the component with a scan tool. The circuit status parameter changes from OK or Not Ran to Fault if there is a condition with the circuit or a connection.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Turbocharger System Description

Electrical Information Reference

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 Bypass Solenoid Valve between Boost and Bypass with a scan tool. You should hear an audible click.
2. 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 Q40 turbocharger bypass solenoid valve.
2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 2 and ground.

⇒	If the test lamp does not illuminate, test the ignition 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 voltage circuit and replace as necessary.

3. Connect a test lamp between the control circuit terminal 1 and the ignition circuit terminal 2.

Note:  The control circuit for the turbocharger bypass solenoid valve is pulled-up to voltage within the ECM, 2.6-4.6 V on the control circuit is normal.

4. Command the Turbocharger Bypass Solenoid Valve between Boost and Bypass then select exit with a scan tool. The test lamp should illuminate and then go OFF.

⇒	If the test lamp is always ON, test the control circuit terminal 2 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 terminal 2 for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 ECM.

5. Test for 2.6-4.6 V between the control circuit terminal 2 and ground.

⇒	If the voltage is not within the specified range, replace the K20 ECM.

6. If all circuits test normal, test or replace the Q40 turbocharger bypass solenoid valve.

Component Testing

1. Ignition OFF, disconnect the harness connector at the Q40 turbocharger bypass solenoid valve.
2. Test for 15-20 Ω between the control terminal 2 and the ignition terminal 1 of the Q40 turbocharger bypass solenoid valve.

⇒	If not within the specified range, replace the Q40 turbocharger bypass solenoid valve.

3. Test for infinite resistance between each terminal and the Q40 turbocharger bypass solenoid valve housing.

⇒	If not the specified value, replace the Q40 turbocharger bypass solenoid valve.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.