Code No. P0403: EGR Valve DC Motor Malfunction




OPERATION




FUNCTION




TROUBLE JUDGMENT


Check Condition
Judgment Criterion

FAIL-SAFE AND BACKUP FUNCTION




PROBABLE CAUSES




DIAGNOSIS PROCEDURE


STEP 1. Check EGR valve itself.



  • EGR valve connector check.
  • Check EGR valve itself [Refer to GROUP 17 - Emission Control <DIESEL> - Exhaust Gas Recirculation (EGR) System - EGR Valve (DC motor) Check ].

Q. Is the check result normal?

Go to Step 2.
Repair or replace the connector, or replace the EGR valve assembly.

STEP 2. Check harness between engine-ECU connector terminal EGR+ and EGR valve assembly connector terminal.



  • Check output line for open/short circuit and damage.

Q. Is the check result normal?

Go to Step 3.
Repair or replace the connector, or repair the damaged harness wire.

STEP 3. Check harness between engine-ECU connector terminal EGR- and EGR valve connector terminal.



  • Check output line for open/short circuit and damage.

Q. Is the check result normal?

Go to Step 4.
Repair or replace the connector, or repair the damaged harness wire.

STEP 4. M.U.T.-III diagnosis code



  • After clearing the diagnosis code through M.U.T.-III, start the engine and confirm whether the diagnosis code is set.

Q. Is the diagnosis code set?

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