Engine JAC HFC4DA1-2C. Manual — part 44

Maintenance manual for sunray hfc4da1-2c china-IV diesel engines

175

23.

DTC P0110

Connection for additional air temperature sensor of air mass flowmeter is
short or open.

P0112

Temperature for additional air temperature sensor of air mass flowmeter is
too low.

P0113

Temperature for additional air temperature sensor of air mass flowmeter is
too high.

P1101

Analog output voltage for additional air temperature sensor of air mass
flowmeter is too high or too low.

P1102

Output duty ratio signal level of additional air temperature sensor of air
mass flowmeter is too high or too low.

P1106

Output duty ratio signal cycle of additional air temperature sensor of air
mass flowmeter is too long.

P1107

Output duty ratio signal cycle of additional air temperature sensor of air
mass flowmeter is too short.

Fault Description: Intake air temperature (IAT) sensor is a variable resistance for measurement of engine intake air
temperature. Air temperature sensor possesses a signal circuit and a low reference voltage circuit. ECU provides air
temperature sensor signal circuit with 5V voltage and provides air temperature sensor reference voltage circuit with
grounding. When air temperature sensor is under cold status, sensor resistance value is high. When air temperature
increases, sensor resistance value decreases. In the case of high sensor resistance, voltage of air temperature sensor
signal circuit detected by ECU is high. With decrease of sensor resistance, voltage of air temperature sensor signal
circuit detected by ECU reduces. In the case of too low detected air temperature signal voltage by ECU (it is indicated
that temperature is too high) or too high signal voltage (it is indicated that temperature is too low), DTC for this
occurs.

Differences among temperature, resistance and voltage are shown as the table below:

Temperature

Temperature Sensor Resistance

Temperature Sensor Signal Voltage

Low

High

High

High Low

Low

Diagnosis Hint: Test air temperature sensor under different temperatures for evaluation of sensor errors. In the case of
sensor error, there will be control performance fault. Lay the engine up for one night, D-value between air temperature
sensor and engine coolant temperature sensor displayed values should be within 3°C (5°F). Please refer to
“Temperature and Resistance”. In the case of too high resistance of temperature sensor signal circuit or low reference
voltage circuit, DTC may not occur.

Check for the following conditions:

Check ECU harness connector for poor contact between ECU and temperature sensor

− Terminal looseness

− Poor fit of matching parts

− Locking plate fracture

− Terminal deformation or damage

− Poor contact between terminal and wire

Maintenance manual for sunray hfc4da1-2c china-IV diesel engines

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Check harness damage. If the harness seems to be normal, move relevant connector and harness for intake air
temperature (IAT) sensor and check display about IAT on diagnostic tool. If display of IAT changes, it is indicated that
there is fault in the part.

Fault Tree:

检查传感器连接

做必要的修理

器件问题

更换传感器

检查传感器电阻（检查其是否与车辆

状态一致

接插件问题

检查连续性和绝缘性

Y

N

N

Y

检查是否为ECU插接件问题

Y

做必要的修理

N

电气问题

Y

修理线束

N

联系技术支持

Get the Technical Support.

Repair the harness.

Repair accordingly.

Repair accordingly.

Replace the sensor.

Check sensor connection.

Connector fault

Check sensor resistance (for conformity with vehicle

status).

Component fault

Check ECU for connector faults.

Check continuity and insulating property..

Electrical fault

Maintenance manual for sunray hfc4da1-2c china-IV diesel engines

177

24.

DTC P0300

Multi-cylinder

misfire

P0301 The

1

st

cylinder misfire

P0302 The 2

nd

cylinder misfire

P0303 The

3

rd

cylinder misfire

P0304 The

4

th

cylinder misfire

Fault Description: ECU determines when engine misfire occurs with the help of information from ignition control
(IC) module and camshaft position (CMP) sensors. ECU can detect single misfire via crankshaft speed change for
each cylinder. In the case of some vehicle running condition, too high misfire rate will lead to three way catalytic
converter (TWC) overheating. In the case of three way catalytic converter overheating, MIL will flash. If misfire rate
detected by ECU is enough to make emission level to exceed mandatory standard, DTC occurs. If diagnosis operation
fails in two continuous ignition cycle, control module lightens MIL. Control module records operation condition when
diagnosis is failed. For the first diagnosis failure, control module will keep this information in fault record. If
diagnosis failure occurs during the successive ignition cycle, control module records operation condition under
diagnosis failure and writes the operation condition in frozen fault condition and updates fault record.

Diagnosis Hint: Influence factors for misfire diagnosis—In the case of misfire diagnosis, it is required that all
vehicle parts are under mass production or equivalent. All changes which may influence engine crankshaft speed will
interfere with correct diagnosis for misfire.

In the case of faults in components as follows, misfire diagnosis will pause to avoid incorrect diagnostic
results—intake pressure/throttle position rationality fault; low voltage or open circuit of intake pressure sensor circuit;
high voltage of intake pressure sensor circuit; low voltage or open circuit of coolant temperature sensor circuit; high
voltage of coolant temperature sensor circuit; high voltage of throttle position sensor; low voltage of throttle position
sensor; signal interference of crankshaft position sensor circuit; no signals in crankshaft position sensor circuit; no
signals in camshaft position sensor circuit; camshaft position sensor rationality fault; high voltage or open circuit of
intake air temperature sensor circuit; low voltage of intake air temperature sensor circuit; no signals in vehicle speed
sensor.

Severe vibration which is not caused by engine may lead to setting fault (vibration source may lead to wears or
damages to brake discs with different thicknesses and additional drive belts).

Maintenance manual for sunray hfc4da1-2c china-IV diesel engines

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Fault Tree:

关闭点火开关并检查喷油器接插件

接插件问题

做必要的修理

曲轴位置传感器间隙问题？

N

Y

检查曲轴位置传感器间隙

检查减震皮带轮与传感器

Y

重新调整曲轴减震皮带轮安装，
还不行，更换减震皮带轮并进行

齿讯学习

皮带轮与传感器是否干涉

调整曲轴位置传感器间隙

（0.6~0.7mm）

N

Y

检查曲轴位置传感器

N

曲轴位置传感器问题

Y

更换曲轴位置传感器

联系技术支持

N

Get the Technical Support.

Repair accordingly.

Connector fault

Turn off ignition switch and check fuel injector connectors.

Check crankshaft position sensor clearance.

Are faults in crankshaft position sensor clearance?

Check damping belt pulley and sensor.

Check belt pulley and sensor for interference.

Check crankshaft position sensor.

Faults are in crankshaft position sensor.

Adjust clearance of crankshaft position sensor

(0.6mm~0.7mm)

Readjust installation of crankshaft damping belt

pulley. If faults occur again, replace damping

belt pulley and carry out gear message learning

Replace crankshaft position sensor.