DEF SCR SYSTEM (DCU)
5–310
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 engine coolant
temperature (actual measured
value) is 50
C {122
F}, check if
the temperature output by the
engine coolant temperature sen-
sor 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.
5
Inspect the air
flow sensor
1.
Check the installation of the
air flow sensor.
2.
Make sure there is no dirt or
damage to the air flow sen-
sor.
Failure found:
Go to YES.
No failure
found: Go to
NO.
If dirt, clog-
ging or dam-
age in the
sensing unit
was found,
replace the air
flow sensor.
Perform "After-
inspection
work" of
INFORMA-
TION section.
Go to step 6.
6
Inspect the
boost pressure
sensor
1.
Check the installation of the
boost pressure sensor.
2.
Make sure there is no dirt,
clogging or damage in the
sensing unit of the boost
pressure sensor.
Failure found:
Go to YES.
No failure
found: Go to
NO.
If dirt, clog-
ging or dam-
age in the
sensing unit
was found,
replace the
boost pressure
sensor.
Perform "After-
inspection
work" of
INFORMA-
TION section.
Go to step 7.
7
Inspect the
boost pressure
sensor output
signal [Hino-
DX]
Select [Actual boost pressure]
from [Data Monitor] on the menu.
Race the engine from idle to No-
Load Maximum and check if the
boost pressure output signal var-
ies.
<Standard values>
There is no abnormality in the
sensor output signal. (The pres-
sure sensor signal changes
according to the engine speed)
There is no
abnormality in
the sensor out-
put signal: Go
to YES.
There is
abnormality in
the sensor out-
put signal: Go
to NO.
Go to step 8.
Replace the
boost pressure
sensor
Perform "After-
inspection
work" of
INFORMA-
TION section.
DTC: P2204
NOx sensor (SCR upstream) - Feedback
Inspection Procedure
Step
Action
Description
Judgement
Check
(Yes/No)
Yes
No
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 ...