ENGINE (J05E)/TROUBLESHOOTING
2–528
DTC: P0421
EN01H02127030602016081
P0421: Determination of ATC deterioration
INFORMATION
1.
Technical description
<Description of malfunction>
•
If post injection is performed normally but the ATC (oxidation catalyst) is not generating heat, the engine ECU
detects abnormality as ATC functional deterioration.
2.
DTC set condition
(1)
DTC detection condition
•
The vehicle speed is 0 km/h.
•
A change in the engine revolution is 312 r/min/sec or less.
•
A change in the fuel injection quantity is 312 mm
3
/st/sec or less.
•
A change in the fuel pressure is 93.7 MPa/sec or less.
•
The target operating current of the fuel pump is not less than 1500 mA but not more than 1800 mA.
(2)
Judgement criteria
•
A change in the operating current of the fuel pump upon post injection exceeds the specified value.
•
Malfunction determination time: 10 seconds
3.
Reset condition
•
Immediately after normal status is resumed
4.
Indication, warning or system control regulation when the DTC is set.
•
MIL: ON
•
SVS light: OFF
5.
Symptoms on the vehicle when the DTC is set
<Symptoms on the vehicle due to backup control (fail safe function)>
•
–
<Symptoms on the vehicle due to malfunction>
•
–
6.
Pre-inspection work
•
Check that the battery voltage is in the normal range.
7.
After-inspection work
•
Clear all past DTCs.
•
Check that no DTC is detected after test drive.
8.
Estimated failure factors
•
ATC deterioration caused by use of low-grade fuel
•
Contamination in the sensing area of the exhaust gas temperature sensor (DPF inlet), improper installation of sen-
sors
