Code No. P0406: Exhaust Gas Recirculation Valve Position Sensor Circuit High Input








OPERATION



  • A power voltage of 5 V is applied to the exhaust gas recirculation valve assembly power terminal (terminal No. 3) from the engine-ECU (terminal No. 71) and earthed to the engine-ECU (terminal No. 81) from the exhaust gas recirculation valve assembly (terminal No. 2).
  • The sensor signal is inputted to the engine-ECU (terminal No. 57) from the exhaust gas recirculation valve assembly output terminal (terminal No. 1).

FUNCTION



  • The exhaust gas recirculation valve assembly detects the position of the exhaust gas recirculation valve and sends the signal to the engine-ECU.
  • Based on the signal, the engine-ECU performs the feedback control of the exhaust gas recirculation valve.

TROUBLE JUDGMENT


Check Conditions
  • Battery positive voltage is 8 - 16 V
  • 2 seconds later after the ignition switch has been in "ON" position or the engine has started up.
Judgment Criterion
  • The exhaust gas recirculation valve position sensor output voltage is 4.80 V or more.

PROBABLE CAUSES



  • Failed exhaust gas recirculation valve position sensor
  • Open circuit or harness damage in exhaust gas recirculation valve position sensor circuit or loose connector contact
  • Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list

  • Refer to Data List Reference Table .

  1. Item 16: Exhaust gas recirculation valve position sensor

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: B-02 exhaust gas recirculation valve assembly connector

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

STEP 3. Perform resistance measurement at B-02 exhaust gas recirculation valve assembly connector.

  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Resistance between terminal No. 2 and earth.
OK: Continuity (2 Ω or less)

Q. Is the check result normal?
Go to Step 7 .
Go to Step 4 .

STEP 4. Connector check: D-213 engine-ECU connector

Q. Is the check result normal?
Go to Step 5 .
Repair or replace the connector.

STEP 5. Check harness between B-02 (terminal No. 2) exhaust gas recirculation valve assembly connector and D-213 (terminal No. 81) engine-ECU connector.

  • Check earthing line for open circuit and damage.

Q. Is the check result normal?
Go to Step 6 .
Repair the damaged harness wire.

STEP 6. M.U.T.-III data list

  • Refer to Data List Reference Table .

  1. Item 16: Exhaust gas recirculation valve position sensor

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. When the engine-ECU is replaced, write the chassis number (Refer to GROUP 00 - Precautions Before Service - How to Perform Chassis Number Writing ). After replacing the engine-ECU, register the injector identification code and learn fuel injection (Refer to GROUP 00 - Precautions Before Service - What The Common Rail Engine Learns ). After registering the injector identification code, the vehicle equipped with the closed type DPF carries out the forcible DPF regeneration. (Refer to GROUP 17 - Diesel Particulate Filter (DPF) System - Forcible DPF Regeneration ).

STEP 7. M.U.T.-III data list

  • Refer to Data List Reference Table .

  1. Item 16: Exhaust gas recirculation valve position sensor

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 exhaust gas recirculation valve assembly.