Hino 238, Workshop Manual

Page: 712 / 919

DEF SCR SYSTEM (DCU) 5–146
DTC: P204C
EN01H16F02040F03001033
DTC: P204C DEF pressure sensor - out of range (Out of range low)
INFORMATION
1. Technical description
• The pressure sensor in the DEF pump is used to confirm the pressure in the DEF pump.
•
A short-circuit or disconnection in the DEF pump pressure sensor is detected with the DCU.
<Description of malfunction>
•
Failure of the pressure sensor in the DEF pump is detected.
2. DTC set condition
(1) DTC detection condition
Starter switch ON.
(2) Judgement criteria
DEF pump pressure sensor circuit voltage
<
0.25 V for more than 0.4 sec.
3. Reset condition
•
After having restored to the normal conditions.
4. Indication, warning or system control regulation when the DTC is set.
•
MIL: ON
•
DEF injection is stopped.
•
NOx purification function is stopped.
5. Symptoms on the vehicle when the DTC is set
<Symptoms on the vehicle due to backup control (fail safe function)>
•
Exhaust gas purification function has deteriorated.
<Symptoms on the vehicle due to malfunction>
•
–
6. Pre-inspection work
•
Check if the battery voltage is in the normal range.
7. After-inspection work
• Clear all past DTCs.
•
Check if no DTC is stored after test drive.
Supply module
(DEF pump)
DCU
LFQ
(PSR+)
LFR
LGD
(PSRS)
(PSR+)
(PSRS)
LFP LGF
(PSR-)
(PSR-)
LFJ
(PMP+)
LFL
LG8
(PMPS)
(PMP+)
(PMPS)
LFK LGA
(PMP-)
(PMP-)
LFM LGB
(PMV+)
(PMV+)
LFN LGC
(PMV-)
(PMV-)
LGE
LG9
SAPH16F020400095