DTC P0400-00: Exhaust Gas Recirculation "A" Flow; DTC P04019C: Exhaust Gas Recirculation "A" Low / Insufficient Flow; DTC P04029B: Exhaust Gas Recirculation "A" High/Excessive Flow [10/2020 - 08/2021]: Description
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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 | Note |
|---|---|---|---|---|---|---|
| P040000 | 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 | SAE Code: P0400 |
| P04019C | Exhaust Gas Recirculation "A" Low / Insufficient Flow | 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 41.8 kPa (6.06 psi) when the EGR valve assembly is not operating (1 trip detection logic). |
|
Comes on | DTC stored | SAE Code: P0401 |
| P04029B | Exhaust Gas Recirculation "A" High/Excessive Flow | 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 41.8 kPa (6.06 psi) or more when the EGR valve assembly is not operating (1 trip detection logic). |
|
Comes on | DTC stored | SAE Code: P0402 |
HINT:
DTC P04019C or DTC P04029B will only be stored when DTC P040000 is stored in the second trip.