• Perform the Diagnostic System Check prior to using this diagnostic procedure:Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis:Strategy Based Diagnosis
• An overview of each diagnostic category can be found here:Diagnostic Procedure Instructions

For an overview of the component/system, refer to:Compressor Air Intake Turbocharger System Description

The turbocharger bypass valve is a pressure relief valve in the intake system. It short-circuits the inlet and the outlet of the fresh air side of the turbocharger. This is used to maintain the rotational energy of the turbine when the throttle valve is quickly closed and the compressed air would have nowhere to go. The bypass valve allows the air to be pumped in circles which avoids pressure spikes.

• Ignition=OnorEngine=Running
• Engine=Not cranking
• System Voltage=Greater than 11 V
• Turbocharger Bypass Solenoid Valve Command=On and Off—At least 1 time(s) during the drive cycle

Frequency the DTC runs=Continuously—After the running conditions are met

Control Circuit=Commanded state does not match the actual state—For greater than 2 s

DTCs listed in the DTC Descriptor category=Type A DTC—Additional actions taken:

Warning Message=Reduced Engine Power

DTCs listed in the DTC Descriptor category=Type A DTC

Engine Controls Schematics

Master Electrical Component List

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

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Control Module References

1. Ignition » On / Vehicle » In Service Mode
2. Perform the scan tool control function:Turbocharger Bypass Solenoid Valve»On and Off

   Verify the scan tool parameter:

• Turbocharger Bypass Solenoid Valve Control Circuit Low Voltage Test Status=OKorNot Run
• Turbocharger Bypass Solenoid Valve Control Circuit Open Test Status=OKorNot Run
• Turbocharger Bypass Solenoid Valve Control Circuit High Voltage Test Status=OKorNot Run
• If not the specified state

  Refer to: Circuit/System Testing

• If the specified state
3. Perform the scan tool control function:Turbocharger Bypass Solenoid Valve»On and Off

   Verify a click can be heard or felt at the following component(s) when the scan tool control function was commanded:Q40 Turbocharger Bypass Solenoid Valve

• If a click cannot be heard or felt

  Refer to: Circuit/System Testing

• If a click can be heard or felt
4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

   Verify the DTC does not set.

• If the DTC sets

  Refer to: Circuit/System Testing

• If the DTC does not set
5. All OK.

1. Ignition/Vehicle & All vehicle systems » Off
2. Disconnect the electrical connector:Q40 Turbocharger Bypass Solenoid Valve
3. Ignition » On / Vehicle » In Service Mode
4. Verify a test lamp turns On between the test points:Ignition circuit terminal 1&Ground
• If the test lamp does not turn On and the circuit fuse is OK
1. Ignition/Vehicle » Off & Remove » Test lamp
2. Test for less than 2 Ω between the test points:Ignition circuit terminal 1&Output terminal@Fuse
• If 2 Ω or greater » Repair the open/high resistance in the circuit.
• If less than 2 Ω » Verify the fuse is OK and there is voltage at the fuse.
• If the test lamp does not turn On and the circuit fuse is open
1. Ignition/Vehicle » Off & Remove » Test lamp
2. Ignition » On / Vehicle » In Service Mode
3. Replace the component:Fuse
4. Verify the fuse does not open.
• If the fuse opens and there are components connected to the circuit » Disconnect a component and repeat procedure starting at step 4.3
• If the fuse opens with all components disconnected from the circuit » Repair the short to ground on the circuit.
• If the fuse does not open after disconnecting a component from the circuit » Replace the component disconnected last.
• If the fuse does not open.

Note: It may be necessary to use a scan tool control function to operate a component.

5. Operate the component:Each component on the circuit—One at a time

Verify the fuse does not open when any of the components are activated.

• If the fuse opens » Replace the component that caused the fuse to open when activated.
• If the fuse does not open.
6. All OK.
• If the test lamp turns On
5. Verify a test lamp does not turn On between the test points:Control circuit terminal 2&Ignition circuit terminal 1
• If the test lamp turns On
1. Ignition/Vehicle » Off & Remove » Test lamp
2. Test for infinite resistance between the test points:Control circuit terminal 2@Component harness&Ground
• If less than infinite resistance » Repair the short to ground on the circuit.
• If infinite resistance » Replace the component:K20 Engine Control Module
• If the test lamp does not turn On
6. Perform the scan tool control function:Turbocharger Bypass Solenoid Valve»On

   Verify a test lamp turns On between the test points:Control circuit terminal 2&Ignition circuit terminal 1

• If the test lamp does not turn On
1. Ignition/Vehicle » Off & Remove » Test lamp
2. Disconnect the appropriate electrical connector:@K20 Engine Control Module
3. Ignition » On / Vehicle » In Service Mode
4. Test for less than 1 V between the test points:Control circuit terminal 2@Component harness&Ground
• If 1 V or greater » Repair the short to voltage on the circuit.
• If less than 1 V
5. Ignition/Vehicle & All vehicle systems » Off
6. Test for less than 2 Ω between the test points:Control circuit terminal 2@Component harness&The other end of the circuit
• If 2 Ω or greater » Repair the open/high resistance in the circuit.
• If less than 2 Ω » Replace the component:K20 Engine Control Module
• If the test lamp turns On
7. Test or replace the component:Q40 Turbocharger Bypass Solenoid Valve

1. Ignition/Vehicle » Off
2. Disconnect the electrical connector:Q40 Turbocharger Bypass Solenoid Valve
3. Test for 10 to 14 Ω between the test points:Control terminal 2&Ignition terminal 1
• If not between 10 and 14 Ω

  Replace the component:Q40 Turbocharger Bypass Solenoid Valve

• If between 10 and 14 Ω
4. Test for infinite resistance between the test points:Each terminal of the component&The component's housing
• If less than infinite resistance

  Replace the component:Q40 Turbocharger Bypass Solenoid Valve

• If infinite resistance
5. All OK.

1. Ignition/Vehicle » Off
2. Disconnect the electrical connector:Q40 Turbocharger Bypass Solenoid Valve
3. Connect a 10 A fused jumper wire between the test points:Ignition terminal 1&12 V

Caution: Complete the testing as quickly as possible in order to prevent overheating and damaging the component.

4. Momentarily connect a jumper wire between the test points:Control terminal 2&Ground

Verify the component turns On and Off when connecting and disconnecting the jumper wire:Q40 Turbocharger Bypass Solenoid Valve

• If the component does not turn On and Off

  Replace the component:Q40 Turbocharger Bypass Solenoid Valve

• If the component turns On and Off
5. All OK.

Perform the Diagnostic Repair Verification after completing the repair:Diagnostic Repair Verification

• Turbocharger Bypass Valve Solenoid Replacement—Q40 Turbocharger Bypass Solenoid Valve
• For control module replacement, programming, and setup refer to:Control Module References