P0034
DTC P0033, P0034, or P0035
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC P0033
- Turbocharger Bypass Valve Solenoid Control Circuit
DTC P0034
- Turbocharger Bypass Valve Solenoid Control Circuit Low Voltage
DTC P0035
- Turbocharger Bypass Valve Solenoid Control Circuit High Voltage
Diagnostic Fault Information
Circuit/System Description
The BorgWarner(TM) dual-scroll turbocharger (TC) incorporates a wastegate that is controlled by a pressure differential, that is determined by the engine control module (ECM) by means of a PWM solenoid, in order to regulate the pressure ratio of the compressor. A compressor bypass valve also controlled by the ECM by utilizing a remotely mounted solenoid is integrated into the unit to prevent compressor surging and damage from vibrations by opening during abrupt closed throttle conditions. When the valve is open during closed throttle deceleration conditions, the bypass valve allows the air to recirculate in the turbocharger and maintain compressor speed. Within a calibrated range during the closed throttle event, or upon a wide open throttle command the valve will then close to optimize turbo response. The TC bypass valve solenoid has the following circuits:
* An ignition 1 voltage circuit
* The turbocharger bypass valve control circuit
As engine load and RPM increases the TC Bypass Solenoid parameter should remain commanded ON by the ECM. As soon as the throttle closes the TC Bypass Solenoid parameter should be commanded OFF by the ECM, in order to allow the turbocharger bypass valve to open and allow the TC air to recirculate, thereby preventing compressor surging.
Conditions for Running the DTCs
* The engine speed is greater than 80 RPM.
* The battery voltage is between 10-18 volts.
* The bypass valve must be activated in order to set the open and short to ground faults.
* This DTC runs continuously within the enabling conditions.
Conditions for Setting the DTCs
The ECM detects an open, a short to ground, or a short to voltage on the TC bypass valve solenoid control circuit for greater than 4 seconds continuously, or 50 seconds cumulative.
Action Taken When the DTCs Set
DTC P0033, P0034, P0035, are Type B DTCs.
Conditions for Clearing the MIL/DTCs
DTC P0033, P0034, P0035, are Type B DTCs.
Diagnostic Aids
* A restriction that exists in the exhaust system will hinder the performance of the engine and the turbocharger. Refer to Restricted Exhaust. Restricted Exhaust
* For additional turbocharger and boost system information, refer to Turbocharger System Description and Boost Control System Description.
Circuit/System Verification
* Inspect for Improper routing or connecting of the vacuum hoses on the TC bypass valve solenoid.
* Use the scan tool output controls to command the TC Bypass Solenoid parameter ON and OFF. An audible click should be heard and felt.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the TC bypass valve solenoid.
2. Ignition ON, verify that a test lamp illuminates between the voltage supply circuit terminal 2 and ground.
Important: If the ignition fuse is open, it will be necessary to test the spliced voltage supply circuits and the components for a short to ground.
• If a test lamp does not illuminate test the voltage supply circuit for a short to ground or an open/high resistance.
3. Connect a test lamp between the control circuit terminal 1 and the voltage supply circuit terminal 2.
4. Command the TC bypass solenoid ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
• If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the ECM.
• If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
5. If the circuits test normal, replace the TC bypass valve solenoid.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests
* Charge Air Bypass Valve Solenoid Replacement
* Refer to Programming and Relearning for ECM setup and programming. Programming and Relearning