DTC P2021: TGV Position Sensor/Switch Circuit Low Bank 2: Notes

1. - 

DTC detecting condition: 

Immediately at fault recognition

Trouble symptom: 

• Improper idling
• Engine stall
• Poor driving performance

Wiring diagram: 

Engine Electrical System Ref. to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK DTC  .
   1. Turn the ignition switch to ON.
   2. Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine]. Ref. to COMMON (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)

   Is DTC P06B1 displayed? (Current code)

   Yes  : Check for DTC P06B1. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)>DTC P06B1 SENSOR POWER SUPPLY "A" CIRCUIT LOW

   No  : Go to  2.

2. CHECK DTC  .

   Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine]. Ref. to COMMON (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)

   Is DTC P06B2 displayed? (Current code)

   Yes  : Check for DTC P06B2. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)>DTC P06B2 SENSOR POWER SUPPLY "A" CIRCUIT HIGH

   No  : Go to  3.

3. CHECK DATA MONITOR  .
   1. Start the engine.
   2. Using the Subaru Select Monitor, read the value in [TGV Position Sensor L].
      NOTE:

      For detailed operation procedures, refer to "COMMON (DIAGNOSTICS)". Ref. to  COMMON (DIAGNOSTICS)>DATA MONITOR 

   Is the value in [TGV Position Sensor L] less than 0.2 [V]?

   Yes  : Go to  4.

   No  : Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

   NOTE:

   In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause. 

4. CHECK POWER SUPPLY OF TUMBLE GENERATOR VALVE ACTUATOR LH  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the connector from tumble generator valve actuator LH.
   3. Turn the ignition switch to ON.
   4. Measure the voltage between tumble generator valve actuator LH connector and engine ground.

      Connector & terminal 

      (E110) No. 3 (+) - Engine ground (-):

   Is the voltage 4.5 V or more?

   Yes  : Go to  5.

   No  : Repair the following item.

   • Open circuit in harness between ECM connector and tumble generator valve actuator LH connector
   • Poor contact of ECM connector
   • Poor contact of J/C
5. CHECK HARNESS BETWEEN ECM AND TUMBLE GENERATOR VALVE ACTUATOR LH CONNECTOR (OPEN)  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the connector from ECM.
   3. Measure the resistance of harness between ECM connector and tumble generator valve actuator LH connector.

      Connector & terminal 

      (E51) No. 6 - (E110) No. 1:

   Is the resistance less than 1 Ω?

   Yes  : Go to  6.

   No  : Repair the open circuit in harness between ECM connector and tumble generator valve actuator LH connector.

6. CHECK HARNESS BETWEEN ECM AND TUMBLE GENERATOR VALVE ACTUATOR LH CONNECTOR (SHORT TO GROUND)  .

   Measure the resistance between the ECM connector and engine ground.

   Connector & terminal 

   (E51) No. 6 - Engine ground:

   Is the resistance 1 MΩ or more?

   Yes  : Go to  7.

   No  : Repair the short circuit to ground in harness between ECM connector and tumble generator valve actuator LH connector.

7. CHECK FOR POOR CONTACT  .

   Check for poor contact of ECM and tumble generator valve actuator LH connector.

   Is there poor contact of ECM or the tumble generator valve actuator LH connector?

   Yes  : Repair the poor contact of ECM or tumble generator valve actuator LH connector.

   No  : Replace the tumble generator valve actuator LH. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>TUMBLE GENERATOR VALVE ACTUATOR

   NOTE:

   The tumble generator valve actuator cannot be disassembled.