Hino 238, Workshop Manual

Page: 317 / 919

ENGINE CONTROL SYSTEM (J08E) 4–1094
CHECKLIST: P226C
DTC: P226C Boost pressure slow response Inspection procedure
Step Action Description Judgement
Check
(Yes/No)
Yes No
1
Check the
response
delay of the
VNT controller
[Hino-DX]
Check the time lag (following
characteristics) of the target VNT
position and actual VNT position.
! CAUTION
Perform the inspection while
the engine is stopped to avoid
engine damages.
<Inspection procedure>
(1) Select [Check functions].
(2) Select [VNT check].
(3) Click [Check start].
(4) Click [VNT opening UP]:
• Inspect the response delay
at each step of the Target
VNT position and Actual
VNT position from 0 to 90
%.
(5) Click [VNT opening DOWN]:
• Inspect the response delay
at each step of the Target
VNT position and Actual
VNT position from 0 to 90
%.
HINT
The VNT opening position
changes of 10 % per step
between 0
–
90 %.
<Standard values>
The response delay should be
less than 3 seconds.
The measure-
ments meet
the standard
value: Go to
YES.
The measure-
ments do not
meet the stan-
dard value: Go
to NO.
Go to step 2.
Replace the
turbocharger.
Perform "After-
inspection
work" of
INFORMA-
TION section.