P0401

DTC P0401: Exhaust Gas Recirculation (EGR) Flow Insufficient Detected

System / Wiring Diagram:

DTC Confirmation Procedure (DTC P0401)

WARNING:
- When performing a road test, select a place where there is no traffic or possibility of a traffic accident and be very careful during testing to avoid occurrence of an accident.
- Road test should be carried out with 2 persons, a driver and a tester, on a level road.

NOTE:
Check to make sure that the following conditions are satisfied when using this DTC confirmation procedure.
- Intake air temp.: Between -10 °C and 70 °C (14 °F and 158 °F)
- Altitude (barometric pressure): 2020 m, 6650 ft or less (540 mmHg, 72 kPa or more)

1. With ignition switch turned OFF, connect scan tool.
2. Turn ON ignition switch and clear DTC using scan tool.
3. Start engine and warm up to normal operating temperature.
4. Drive vehicle at 40 mph (60 km/h) or more (engine speed; 2000 - 3000 r/min.).
5. Keep the vehicle speed for 10 min. (Throttle valve opening is kept constant in this step.)
6. Stop vehicle.
7. Check if DTC / pending DTC exists using scan tool. If not, check if EGR system monitoring test has completed using scan tool. If not in both of the checks (i.e., no DTC / pending DTC and EGR system monitoring test not completed), check vehicle conditions (environmental) and repeat Steps 3 through 6.

Step 1:

Step 2 - 8:

Step 8 - 10:

DTC Troubleshooting