DTC P0401-9C: Exhaust Gas Recirculation "A" Low / Insufficient Flow [06/2018 - 07/2019]: 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 |
|---|---|---|---|---|---|---|
| P0401-9C | Exhaust Gas Recirculation "A" Low / Insufficient Flow | Change in intake manifold pressure is small when the EGR valve opened and closed during fuel cut operation (2 trip detection logic). |
|
Comes on | DTC stored | SAE Code: P0401 |