P011A: Engine Coolant Temperature Sensor - Rationality; Dtc: P011A - Hino Motors HINO 155 series Workshop Manual

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DTC: P011A

P011A: Engine coolant temperature sensor - rationality

INFORMATION
Body earth
Body earth
1. Technical description
• Two engine coolant temperature sensors are installed in thermostat case and constantly measure the engine cool-
ant temperature.
• Although some exhaust gas components operate after the engine coolant temperature has risen to some degree
(engine warm up), when an engine coolant temperature sensor reads a value lower than the actual temperature, it
means it is not working properly. Diagnosis is therefore required to detect if there is something wrong with the char-
acteristics of the engine coolant temperature sensor.
<Description of malfunction>
• Incompatible readings from the 2 engine coolant temperature sensors are detected.
2. DTC set condition
(1) DTC detection condition
• Engine speed is at least 500 r/min or engine is stopped.
• Battery voltage is in the range of 10 V to 16 V.
• Intake air temperature is -20 C {-4 F} or higher.
(2) Judgement criteria
• Difference between the 2 engine coolant temperature sensors is at least 15 C {59 F}.
3. Reset condition
• Problem does not recur in the same driving cycle.
• Normal operation is restored when in subsequent driving cycles, readings are in the normal range within the above
detection conditions.
• Three driving cycles must be deemed normal for MIL to be OFF.
4. Indication, warning or system control regulation when the DTC is set.
• MIL: ON
• SVS light: OFF
ENGINE (J05E)/TROUBLESHOOTING
Coolant temperature
sensor
X66 (THW)
Z5G (E)
Coolant temperature
sensor 2
(THW2)
XS1
(E22)
ZKP
Engine ECU
10mA X28 (THW)
10mA
ZJQ (E5)
X3Q (SL)
10mA XDN (THWO)
10mA
ZD6 (E3)
EN01H02127030602016046
SHTS021270300231