Hino 238, Workshop Manual

Page: 726 / 919

DEF SCR SYSTEM (DCU) 5–160
DTC: P205B
EN01H16F02040F03001035
DTC: P205B DEF tank temperature sensor - rationality
INFORMATION
1. Technical description
• DEF tank temperature sensor rationality is checked by comparison with Ambient air temperature.
<Description of malfunction>
• Failure of DEF tank temperature sensor is detected.
2. DTC set condition
(1) DTC detection condition
Starter switch ON.
Difference between Ambient air temperature and Exhaust gas temperature (SCR inlet):
<
8

C {46.4

F}
Difference of Ambient air temperature between Engine coolant temperature (from Engine ECU):
<
8

C {46.4

F}
Difference between Exhaust gas temperature (SCR inlet) and Engine coolant temperature (from Engine ECU):
<
8

C
{46.4

F}
(2) Judgement criteria
Difference between DEF tank temperature and Ambient air temperature:
>
50

C {122

F} for 2 sec.
Common rail_
CAN_J/C3
Common rail_
CAN_J/C1
NOx
sensor 1
NOx
sensor 2
%JU
%JZ
%JQ
%KF
%JV
(CA2H)
(CA2L)
(CA2H)
(CA2L)
(CA3H)
%KH
%KG
(CA3L)
(CA3H)
%KE
(CA3L)
%KM
(CA3H)
%KL
(CA3L)
%JR
(CA2H)
%JW
(CA2L)
LE9
LE8 (CANH) (CANL)
H
L
H
L
H
L
%JS
(CA2H)
%JX
(CA2L)
LED
LEC
(CANH)
(CANL)
DEF sensor
(DEF tank
temperature
sensor)
H
L
%KP
(CA3H)
%KN
(CA3L)
LEK
LEJ
(CANH) (CANL)
H
L
Engine
ECU
DCU
#S5
#S7
#S5
#S7
#AW
#AV
#AW
#AV
LCM
H
L
(CA1H)
LCN
LF5
LF6
(CA1L)
(CAL1)
#CP #CP
#CQ
#CQ
#SD #SD
#SF
#SF
K6V
(CANH)
K6W (CANL)
H
L
(CAH1)
LEY
LEZ
250K
500K
(CAL0)
(CAH0)
LJM LJN
(CAH1) (CAL1)
LJK
LJL
(CAH0)
(CAL0)
BCU
Engine coolant
temperature sensor 1
KTU KTD
E23
E24
E23
(WTM-)
(WTM+)
(AGD5)
(THW+)
KOU
KTD
KOU
LE4
LE5
LFG
LFH
(FAT-)
(FAT+)
LGJ
LGK
LNM
LNN
(HH1-)
(HH1+)
(ATS-)
(ATSS+)
(EXT-)
(EXT+)
(ER+)
(ER-)
LQ
U
LQV
Ambient air
temperature
sensor
Exhaust gas
temperature
sensor
(SCR inlet)
External
resistance
&RE
(CA2H)
&RJ
(CA2L)
&RD
(CA2H)
&RH
(CA2L)
&RF
&RK
(CA2H) (CA2L)
Common rail_
CAN_J/C2
SAPH16F020400105