DTC P0400: Exhaust Gas Recirculation Flow; DTC P0401: Exhaust Gas Recirculation Flow Insufficient Detected; DTC P0402: Exhaust Gas Recirculation Flow Excessive Detected [08/2022 - ]: Description
Based on the driving conditions, the ECM regulates the volume of exhaust gas that is recirculated to each engine cylinder in order to lower the combustion temperature and reduce NOx emissions. The ECM monitors signals such as engine speed, engine coolant temperature, electric load, and vehicle speed. When the EGR permission conditions are met, the ECM controls the opening of the EGR valve linearly through signals to the EGR step motor.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Memory |
|---|---|---|---|---|---|
| P0400 | Exhaust Gas Recirculation "A" Flow | During fuel cut, when the change in intake manifold pressure when the EGR valve assembly is operating and when not operating is insufficient (2 trip detection logic). |
|
Comes on | DTC stored |
| P0401 | Exhaust Gas Recirculation Flow Insufficient Detected | During fuel cut, when the change in intake manifold pressure when the EGR valve assembly is operating and when not operating is insufficient, the intake manifold pressure is less than 26.28 kPa when the EGR valve assembly is not operating (1 trip detection logic). |
|
Comes on | DTC stored |
| P0402 | Exhaust Gas Recirculation Flow Excessive Detected | During fuel cut, when the change in intake manifold pressure when the EGR valve assembly is operating and not operating is insufficient, the intake manifold pressure is 26.28 kPa or more when the EGR valve assembly is not operating (1 trip detection logic). |
|
Comes on | DTC stored |
HINT:
DTC P0401 or DTC P0402 will only be stored when DTC P0400 is stored in the second trip.