DEF SCR SYSTEM (DCU)
5–242
10
Inspect the
coolant cut off
valve (DEF
tank heater
valve) unit
Measure the resistance between
the terminals of the coolant cut off
valve (DEF tank heater valve).
<Tester connections>
Coolant cut off valve (DEF tank
heater valve) connector
LDU
–
LDV
<Standard values>
20
C {68
F}; 9.04
–
9.52
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 11.
Replace the
coolant cut off
valve (DEF
tank heater
valve).
Perform "After-
inspection
work" of
INFORMA-
TION section.
11
Inspect the
coolant cut off
valve (DEF
tank heater
valve)
Twenty seconds after the engine
has started, grasp the pipe down-
stream of the coolant cut off valve
(DEF tank heater valve) and
check if the pressure drops.
There is fault
(The pressure
does not fall
out): Go to
YES.
There is no
fault (The
pressure
drops): Go to
NO.
Go to step 12.
Replace the
coolant cut off
valve (DEF
tank heater
valve).
Perform "After-
inspection
work" of
INFORMA-
TION section.
12
Inspect the
DEF sensor
1.
Remove the coolant hose
(upstream, downstream)
from DEF sensor.
2.
Blow air from one side and
make sure it comes out from
the other side.
Failure found:
Go to YES.
No failure
found: Go to
NO.
Replace the
DEF sensor.
Perform "After-
inspection
work" of
INFORMA-
TION section.
Go to step 13.
13
Inspect the
DEF pump
1.
Remove the coolant hose
(upstream, downstream)
from DEF pump.
2.
Blow air from one side and
make sure it comes out from
the other side.
Failure found:
Go to YES.
No failure
found: Go to
NO.
Replace the
DEF pump
Perform "After-
inspection
work" of
INFORMA-
TION section.
Go to step 14.
14
Replace the
DEF tank tem-
perature sen-
sor
Replace the DEF tank tempera-
ture sensor.
Warm up the engine (water temp:
60
C {140
F}: or more) and
check if P20B2 has been
detected in [DCU].
DTC P20B2
has been
detected: Go
to YES.
No DTC has
been detected:
Go to NO.
Replace the
DCU.
Perform "After-
inspection
work" of
INFORMA-
TION section.
Procedure
completed.
Perform "After-
inspection
work" of
INFORMA-
TION section.
DTC: P20B2
DEF tank heater valve stuck
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 ...