Code No. P0243: Waste gate Solenoid Valve System










OPERATION



  • Power is supplied to the waste gate solenoid valve (terminal No. 1) from the engine control relay (terminal No. 2).
  • The engine-ECU (terminal No. 52) makes the power transistor in the unit be in ON position, and that makes currents go on the waste gate solenoid valve (terminal No. 2).

FUNCTION



  • In response to a signal from the engine-ECU, the waste gate solenoid valve controls the supercharging pressure to be introduced into the waste gate actuator of the turbo charger.

TROUBLE JUDGMENT


Check Conditions
  • Engine is running.
  • Battery positive voltage is more than 10 V.
Judgement Criterion
  • The waste gate solenoid valve coil surge voltage (battery positive voltage + 2 V) is not detected after the waste gate solenoid valve is turned off.
FAIL-SAFE AND BACKUP FUNCTION
  • None.

PROBABLE CAUSES



  • Failed waste gate solenoid valve
  • Open/short circuit or harness damage in waste gate solenoid valve circuit or loose connector contact
  • Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III actuator test

  • Item 20: Waste gate solenoid valve
OK: Operating sound can be heard and the valve vibrates

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).
Go to Step 2.

STEP 2. Connector check: A-64 waste gate solenoid valve connector

Q. Is the check result normal?
Go to Step 3.
Repair or replace the connector.

STEP 3. Perform resistance measurement at A-64 waste gate solenoid valve connector.

  • Disconnect connector, and measure at solenoid valve side.
  • Resistance between terminal No. 1 and No. 2.
OK: 29 - 35 Ω (at 20°C)

Q. Is the check result normal?
Go to Step 4.
Replace the waste gate solenoid valve.

STEP 4. Perform voltage measurement at A-64 waste gate solenoid valve connector.

  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal No. 1 and earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 6.
Go to Step 5.

STEP 5. Connector check: A-33X engine control relay connector

Q. Is the check result normal?

    Check and repair harness between A-64 (terminal No. 1) waste gate solenoid valve connector and A-33X (terminal No. 2) engine control relay connector.

    • Check power supply line for open/short circuit.
Repair or replace the connector.

STEP 6. Connector check: B-08 engine-ECU connector

Q. Is the check result normal?
Go to Step 7.
Repair or replace the connector.

STEP 7. Perform voltage measurement at B-08 engine-ECU connector.

  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal No. 52 and earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 8.

    Check intermediate connector A-65, and repair if necessary. If intermediate connector is normal, check and repair harness between A-64 (terminal No. 2) waste gate solenoid valve connector and B-08 (terminal No. 52) engine-ECU connector.

    • Check output line for open/short circuit.

STEP 8. Check harness between A-64 (terminal No. 2) waste gate solenoid valve connector and B-08 (terminal No. 52) engine-ECU connector.

  • Check output line for damage.
note Before checking harness, check intermediate connector A-65, and repair if necessary.

Q. Is the check result normal?
Go to Step 9.
Repair the damaged harness wire.

STEP 9. Check harness between A-64 (terminal No. 1) waste gate solenoid valve connector and A-33X (terminal No. 2) engine control relay connector.

  • Check power supply line for damage.

Q. Is the check result normal?
Go to Step 10.
Repair the damaged harness wire.

STEP 10. M.U.T.-III actuator test

  • Item 20: Waste gate solenoid valve
OK: Operating sound can be heard and the valve vibrates

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).
Replace the engine-ECU.