DEF SCR SYSTEM (DCU)
5–291
CHECKLIST: P2201
DTC: P2201
NOx sensor (SCR upstream) - Performance and
Monitoring capability
Inspection Procedure
Step
Action
Description
Judgement
Check
(Yes/No)
Yes
No
1
Check the
DTC detected
(DCU) [Hino-
DX]
Check if any DTC other than
P2201 (for example P2202,
P2209, U029D) has been
detected in [Engine].
DTC other
than P2201
(for example
P2202, P2209,
U029D) has
been detected:
Go to YES.
No DTC has
not been
detected: Go
to NO.
Go to diagno-
sis procedure
of a related
DTC.
Go to step 2.
2
Inspect the
NOx sensor 1
(SCR
upstream)
1.
Swap the position of the
NOx sensor 1 and 2, and
attach them to the vehicle.
2.
Erase the malfunction his-
tory using Hino-DX.
3.
After a DPR forced regener-
ation, check if P2201 is
detected in the [DCU].
DTC P2201
has been
detected: Go
to YES.
No DTC has
not been
detected: Go
to NO.
Go to step 3.
Replace the
NOx sensor 1.
Perform "After-
inspection
work" of
INFORMA-
TION section.
3
Inspect the
engine cool-
ant tempera-
ture sensor
1.
Check the installation of the
engine coolant temperature
sensor (Looseness and poor
contact).
2.
Make sure there is no dirt or
damage to the engine cool-
ant temperature sensor.
Failure found:
Go to YES.
No failure
found: Go to
NO.
Clean the
engine cool-
ant tempera-
ture sensor
and install it
properly.
If damaged,
replace the
engine cool-
ant tempera-
ture sensor.
Perform "After-
inspection
work" of
INFORMA-
TION section.
Go to step 4.
4
Check the
engine cool-
ant tempera-
ture sensor
output signal
[Hino-DX]
Select [Engine coolant tempera-
ture] from [Data Monitor] on the
menu. When the coolant tempera-
ture (actual measured value) is 50
C {122
F}, check if the tempera-
ture output by the engine coolant
temperature sensor is 50
C {122
F}
<Standard values>
The output value and the mea-
sured value match
The output
value and the
measured
value match:
Go to YES.
The output
value and the
measured
value do not
match: Go to
NO.
Go to step 5.
Replace the
engine cool-
ant tempera-
ture sensor.
Perform "After-
inspection
work" of
INFORMA-
TION section.
Summary of Contents for 238
Page 201: ...ENGINE CONTROL SYSTEM J08E 4 978 Harness disconnection or short circuit ...
Page 215: ...ENGINE CONTROL SYSTEM J08E 4 992 Malfunction of sensor 2 Malfunction of engine ECU ...
Page 301: ...ENGINE CONTROL SYSTEM J08E 4 1078 8 Estimated failure factors Malfunction of engine ECU ...
Page 709: ...DEF SCR SYSTEM DCU 5 143 8 Estimated failure factors DEF pump pressure sensor malfunction ...