Hino 238, Workshop Manual

Page: 311 / 919

ENGINE CONTROL SYSTEM (J08E) 4–1088
DTC: P226C
EN01H16F01030F03001140
P226C: Boost pressure slow response
INFORMATION
1. Technical description
• The VNT actuator steplessly moves the nozzle vane via the REA (Rotary Electric Actuator) and controls turbocharger
speed and boost pressure.
• The sensor inside the REA detects the amount of actuator movement and constantly monitors the nozzle vane target
opening and actual opening.
<Description of malfunction>
• VNT response delay is detected.
2. DTC set condition
(1) DTC detection condition
• 10 minutes after engine start-up
* Estimated boost pressure variation, which is calculated from the engine speed and fuel injection rate, is either
≥
30
kPa/sec {4.4 psi} or
≤
-35 kPa/sec {-5.1 psi}.
* Engine speed fluctuation is less than 100 r/min.
(2) Judgement criteria
•
Difference between [estimated boost pressure
–
actual boost pressure] is either
≥
55 kPa/sec {8.0 psi/sec} or
≤
-
30 kPa/sec {-4.4 psi/sec}.
3. Reset condition
•
After normal operation is restored and the starter switch is on the "LOCK" position.
4. Indication, warning or system control regulation when the DTC is set.
•
MIL: ON
• Diag lamp: OFF
VNT
controller
VNT
actuator
LM8
(AMPU)
LMY
LMZ
(HSPW)
(MPU)
LM4
(AHOU)
LM3
(AHOV)
(HOV)
LM2 LMU
(AHOW) (HOW)
%KQ
(ENG)
%KV
(VNTC)
%KW
(VNTA)
(VNTA)
LM5
LMW
LMV
(AHSG)
(SLGD)
(HSGD)
LM1 LMX
(AHSP)
(AMPW)
(AMPV)
LMT
(MPV)
LM0
(MPW)
KV0
(VNTV)
KV
A
(VNTG)
KV8
(VNTH)
KV9
(VNTL)
L4T
(EGR
V)
L4U
(EGRG)
L4S (EGRL)
L4R (EGRH)
(CANH)
K6W
K6V
(CANL)
(HOU)
LMS LM4 LMS
LM3 LMT
LM2 LMU
%Z3 LMW
LM5 LMV
LM1 LMX
LM8 LMY
LM7 LMZ
LM6 LM0
LM7
LM6
%Z3
T
o
CAN circuit (DPR) (BA-1)
EGR
controller
Engine
ECU
(BA-1)
To CAN circuit (DPR)
SAPH16F010300839