JAC HFC4DA1-2C engine. Instruction — part 10

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

146

9.

DTC P0204

The

4

th

cylinder fuel injector circuit is open.

P0270

The low end of the 4

th

fuel injector is short to the high end.

P0271

The low end of the 4

th

fuel injector is short to the high level.

P0272

Other errors of the 4

th

cylinder fuel injector

P1206

The forward error correction of the 4

th

fuel injector is too large.

P1207

The reverse error correction of the 4

th

fuel injector is too large.

P1212

The dynamic forward error correction of the 4

th

fuel injector is too large.

P1213

The dynamic reverse error correction of the 4

th

fuel injector is too large.

P123C

Other errors of the 4

th

cylinder fuel injector

P123D

Other errors of the 4

th

cylinder fuel injector

P123E

Other errors of the 4

th

cylinder fuel injector

Fault Description: The ECU controls the switching-on circuit of fuel injector directly. The ECU controls the time for
switching on each fuel injector via adopting a device named “Driver” to supply PWM current to each fuel injector
control circuit. The driver owns a feedback circuit, which is monitored by ECU to verify if the control circuit is open
or short. If any failure in the fuel injector control circuit is detected by ECU, the fuel injector control circuit DTC shall
be generated.

Diagnosis Hint: For the failure in wire connector shall trigger the setting of DTC, be sure to check the connectors
relevant to this diagnostic procedure for short circuit of terminal or poor contact of wire, prior to replacement of any
component. Observe the state parameter of relevant fuel injector on the diagnostic tool while shaking the wire and
connector relevant to the test. If any intermittent failure is existed in the tested wire or connector, the relevant failure
shall be displayed on the diagnostic tool.

Performing compression test is helpful for locating the intermittent failure.

Terminal ECU

A17 2

nd

fuel injector “High”

A33 2

nd

fuel injector “Low”

2

nd

fuel injector “High”

2

nd

fuel injector “Low”

4

th

cylinder

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Fault Tree:

Turn off the ignition switch and check the fuel

injector connector.

Connector fault

Repair accordingly.

Disconnect the fuel injector and turn on the ignition

switch.

Does the problem still exist?

Refer to “Inspection of Fuel Injector

Wiring” listed below.

Clear the DTC, turn off the ignition switch, reconnect

the fuel injector and turn on the ignition switch.

Does the problem reoccur?

Replace relevant fuel injector and

update the ECU data.

Repeat the above procedures for other fuel injectors.

Check the wiring of fuel injector.

Check the ECU connector.

Connector fault

Repair accordingly.

Check continuity and insulating property.

Electrical fault

Repair the harness.

Get the Technical Support.

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10.

DTC

P0251

The control line of fuel level control unit is open.

P0252

The ECU internal driver module of fuel level control unit is overheating.

P0253

The control line of fuel level control unit is short to ground.

P0254

The control line of fuel level control unit is short to high level.

Fault Description: The fuel metering unit is for adjusting the fuel supply and the fuel pressure. When the control coil
of metering unit is off, the inlet fuel metering proportional valve of the unit shall be closed, cutting off the fuel
supplied to the high pressure fuel pump plunger component. When the control coil of metering unit is electrified, the
ECU shall change the fuel inlet sectional area of metering component via pulse signal according to the actual demand,
through which, the fuel supplied to the high pressure fuel pump plunger component shall be changed. If the fuel
metering control signal voltage detected by ECU is abnormal, the DTC shall be generated.

Diagnosis Hint: The metering component is mounted at the fuel inlet of high pressure pump. The engine’s fuel
supply shall be affected directly by the opening sectional area of the fuel metering unit control valve. Provided that the
fuel metering unit control line is normally connected, monitor the engine fuel supply amount and pressure while
moving relevant connector and wire to check if any fault is triggered. If any, the indication of fault diagnostic unit
shall change. This is help for locating the intermittent failure.

The intermittent failure may be caused by poor contact of control part. As for poor contact between ECU and fuel
metering unit, please check the ECU harness connector for the following conditions:

− Loose terminal

− Poor matching and connection

− Breakage of keeper

− Distortion or damage of terminal

− Poor contact between terminal and wire

Check the harness for any damage. If the harness appears normal, observe the fuel pressure indicated on the diagnostic
tool while moving relevant connector and harness of fuel metering unit. If the pressure indication changes, there must
be failure in that part.

Terminal ECU

A19

Power supply terminal of fuel metering unit

A49

Signal terminal of fuel metering unit

Control of fuel metering unit

Fuel metering unit

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

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Fault Tree:

Check the connector of fuel metering unit.

Repair accordingly.

Repair accordingly.

Repair the harness.

Repair the fuel metering unit.

Get the Technical Support.

Connector fault

Check the ECU connector.

Connector fault

Check continuity and insulating property.

Electrical fault

Resistance fault

Measure the resistance of fuel metering unit

(it is about 5.3 Ohms at 20℃)

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11.

DTC

P0335

No signal from crankshaft sensor

P0336

False signal from crankshaft sensor

Diagnosis Hint: The signal of crankshaft position (CKP) sensor is used for indicating the rotary speed and position of
crankshaft. The CKP sensor shall generate an AC voltage of different amplitude and frequency. The frequency relies
on the rotary speed of crankshaft and the output AC voltage relies on the crankshaft position. The CKP sensor shall
coordinate with a 58X variable reluctance rotor fixed on the crankshaft. The ECU can synchronize the timing control
for fuel injectors according to the input signals of CKP sensor and camshaft position sensor. The CKP sensor can also
be applied for testing misfire and tachometer indication. The signal circuit and the low reference voltage circuit of
CKP sensor are directly connected to ECU. The shielded and grounded circuit should be grounded. In addition, when
the 1

st

and the 4

th

cylinders are at TDC, the CKP sensor shall also send a signal to ECU. The ECU shall monitor the

signals of CKP sensor and camshaft position sensor to determine whether the 1

st

cylinder is in compression stroke or

not. The circuits between CKP sensor and ECU include:

Signal circuit of CKP sensor

Low reference voltage circuit of CKP sensor

Shielded and grounded circuit

If the number of crankshaft position pulses sent out by the CKP sensor detected by the ECU is incorrect, the DTC
shall be generated.

Diagnosis Hint: There is failure in camshaft position sensor circuit.

CKP sensor variable reluctance rotor is dislocated or incorrectly installed.

Large crankshaft end play leads to dislocation of variable reluctance rotor.

There is blockage between CKP sensor and variable reluctance rotor.

Check connectors of CKP sensor and ECU for any corrosion.

Prior to maintenance, all fragments should be removed from the connector surfaces. Prior to diagnosis or replacement,
please check the connector gaskets to ensure they are properly installed to avoid ingress of any pollutant.

z Poor terminal connection – Check the harness connector for any loose terminal, mismatching, damaged keeper,

improper form or damage, poor contact between terminal and wire. Check if the matched terminal is adopted.
Check if the test tension is appropriate.

z Harness damage – Check the harness for any damage. If the harness appears normal, observe the indication on

the diagnostic tool while moving relevant connector and harness of the sensor. If the indication changes, there
must be failure in that part.

Wheel speed sensor

Signal

Ground

Shielded wire

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z Check if the ground and connection of ECU and engine is reliable and clean. If the DTC is determined to be

intermittent failure, please refer to the fault records to find out when the previous DTC is set.

Terminal ECU

A13

Signal terminal of CKP sensor

A14

Negative signal terminal of CKP sensor

A56

Shielded terminal of CKP sensor

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Fault Tree:

Check the sensor connection.

Connector fault

Repair accordingly.

Check the ECU connector.

Connector fault

Repair accordingly.

Repair the harness.

Electrical fault

Check continuity and insulating property.

The new sensor is connected.

Does the problem still exist?

Replace the target wheel.

The new target wheel is installed.

Does the problem still exist?

Get the Technical Support.

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

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12.

DTC

P0340

No signal from phase sensor

P0341

False signal from phase sensor

Fault Description: The camshaft position (CMP) sensor is a Hall Effect switch. The ECU shall supply 5V voltage to
the 5V reference voltage circuit and also supply grounding for the low reference voltage circuit. The CMP sensor shall
provide a signal voltage to ECU by coordinating with 1X variable reluctance rotor. The ECU shall make use of this
signal voltage to determine the camshaft position. The CMP sensor links the crankshaft with the camshaft position to
facilitate ECU to determine which cylinder the fuel should be injected to. During the rotation of camshaft, the variable
reluctance rotor changes the magnetic field generated by the magnet in sensor and send a signal to ECU via the signal
circuit. The CMP sensor circuit is directly connected to ECU. The CMP sensor can also be adopted to tell which
cylinder has misfire. The circuits between CMP sensor and ECU include:

High reference voltage circuit of CMP sensor

Ground circuit

Camshaft position signal circuit

When no occurrence of minimum camshaft position synchronization is detected by ECU or there is failure in CMP
sensor signal circuit, DTCs shall be generated.

Diagnosis Hint: Prior to maintenance, all fragments should be removed from the connector surfaces. Prior to
diagnosis or replacement, please check the connector gaskets to ensure they are properly installed to avoid ingress of
any pollutant.

Poor terminal connection – Check the harness connector for any loose terminal, mismatching, damaged keeper,
improper form or damage, poor contact between terminal and wire. Check if the matched terminal is adopted. Check
if the test tension is appropriate.

Harness damage – Check the harness for any damage. If the harness appears normal, observe the indication on the
diagnostic tool while moving relevant connector and harness of the sensor. If the indication changes, there must be
failure in that part.

Check if the ground and connection of ECU and engine is reliable and clean. If the DTC is determined to be
intermittent failure, please refer to the fault records to find out when the previous DTC is set.

Terminal ECU

A08

Signal terminal of phase sensor

A57

Negative signal terminal of phase sensor

A35

Shielded terminal of phase sensor

Camshaft position

sensor

5V power supply

CMP signal

Ground

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

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Fault Tree:

Check the sensor connection.

Connector fault

Repair accordingly.

Visually check the sensor.

Sensor fault

Replace the sensor.

Check the ECU connector.

Connector fault

Repair accordingly.

Repair accordingly.

Repair the harness.

Signal fault

Check the signals of camshaft and crankshaft

sensor with oscilloscope if possible.

Check continuity and insulating property.

Electrical fault

Check the target wheel of camshaft.

Fault of target wheel

Replace the target wheel.

Check the positioning of camshaft target wheel.

False positioning of camshaft target wheel

Correct the positioning of target wheel.

Get the Technical Support.

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13.

DTC

P0380

The glow plug works without the command from ECU.

P0382

The glow plug doesn’t work with the command from ECU.

P0383

ECU control line for glow plug is short to ground.

P0384

ECU control line for glow plug is short to high level.

P0670

ECU control line for glow plug is open or its driver module is overheating.

Fault Description: The main part of glow plug is tubular heating element, which is securely and tightly installed
inside the glow plug shell, making it resistant to corrosion and thermal shock. The heating element is composed of
two resistance elements connected in series; they are installed in the top of heat pipe forming respectively a heating
coil and a control coil. The glow plug controller controls over the glow plug via a power relay and electrical switch
group. It can control the heating time of glow plug and also serve as a protection and monitoring device. The higher
level glow plug controller has diagnosis function, so it can distinguish an individual fault of glow plug and indicate it
to the driver. A multilevel socket is equipped on the control input terminal of glow plug controller for connecting with
ECU. To avoid voltage drop, screw pins or plugs should be equipped in the series circuit that is connected with the
glow plug. The post-heating upon a success start can facilitate the uninterrupted speed increase and idling with little
smoke in the process of heating, which can reduce the combustion noise in cold starting. If it fails, the glow plug
protection circuit shall open to avoid overdischarging of battery. If no preheating control signal is detected by ECU or
the detected control signal is inconsistent with the actual, relevant DTCs shall be generated.

Diagnosis Hint: The failure may be caused by poor contact of wire or loose connector. As for poor contact of ECU or
preheating control unit, check the harness connector for the following conditions:

Loose terminal

Poor matching and connection

Distortion or damage of terminal

Poor contact between terminal and wire

Damage of harness – Check the harness for any damage

Terminal ECU

K90

Control signal of preheating relay

K57 Preheating

time feedback signal

Glow plug

Power supply

Preheating control signal

Preheating feedback signal

Main relay

Preheating relay

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

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Fault Tree:

检查预热塞接插件

做必要的修理

接插件问题

做必要的修理

检查ECU接插件

接插件问题

检查连续性和绝缘性

Y

N

Y

N

电气问题

Y

修理线束

更换预热塞

N

问题仍否存在

Y

联系技术支持

Check the connector of glow plug.

Connector fault

Repair accordingly.

Repair accordingly.

Check the ECU connector.

Connector fault

Check continuity and insulating property.

Electrical fault

Repair the harness.

Replace the glow plug.

Does the problem still exist?

Get the Technical Support.

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

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14.

DTC

P0500

Error of vehicle speed sensor acquisition hardware

P0501

The vehicle speed sensor signal is unreliable.

Fault Description: Vehicle speed sensor (VSS) provides vehicle speed signals to ECU. It is a kind of Hall Effect
sensor. When the rotor gear tooth of transmission output shaft passes through the magnetic field of sensor, the VSS
shall generate a signal voltage, whose frequency shall increase with the vehicle speed. The ECU shall convert the
signal voltage into vehicle speed and make use of the vehicle speed signal to determine the working status of vehicle.
If this signal is lost or abnormal, relevant DTCs shall be generated.

Diagnosis Hint: Check the harness for any damage. If the harness appears normal, observe the indication on the
digital multimeter while moving relevant connector and harness of the actuator. If the indication changes in testing,
there must be failure in that part. The intermittent failure may be caused by poor contact, abrasion of wire insulation
or breakage of the wire inside insulation. Make sure the vehicle speed sensor is correctly fixed onto the transmission
housing.

Terminal ECU

K75

VVS input signal

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Fault Tree:

Check the sensor connection.

Connector fault

Repair accordingly.

Check the ECU connector.

Connector fault

Repair accordingly.

Repair the harness.

Electrical fault

Check continuity and insulating property.

Check the VVS.

VVS fault

Replace the VVS.

Get the Technical Support.

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

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15.

DTC

P0504

Unreliable comparison between main and auxiliary brake pedal signals

Fault Description: The brake switch detects the brake pedal action and sends the signal to ECU. The brake switch is
equipped with two switches, viz. main and auxiliary brake switches. When these two signals are input, these signals
are determined by ECU to be normal brake signals. The switch signals are relevant to the accelerator pedal, for
controlling the fuel amount during braking. There should be no failure when you operate the accelerator pedal at the
point of depressing the brake pedal, but the fuel amount shall be reduced when you operate the accelerator pedal with
the brake pedal depressed. If the voltage signal of brake switch is inconsistent with the actual, the DTC shall be
generated.

Diagnosis Hint: Check the wiring connector for poor contact, distorted or damaged terminal.

Terminal ECU

K17

Main brake switch signal

K80

Auxiliary brake switch signal

Main brake switch

Auxiliary brake switch

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Fault Tree:

Check the component connector.

Connector fault

Repair accordingly.

Visually check the component.

Component fault

Replace the component.

ECU connector fault

Repair accordingly.

Check continuity and insulating

property.

Electrical fault

Repair the harness.

Replace the component.

Does the problem still exist?

Get the Technical Support.

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16.

DTC

P0562

Too low battery voltage

P0563

Too high battery voltage

P1617

The engine cannot be shut down with too high internal supply voltage.

P1618

The engine cannot be shut down with too low internal supply voltage.

P1637

Too high voltage in ECU internal power supply module

P1638

Too low voltage in ECU internal power supply module

Fault Description: The ECU monitors the system voltage via the ignition voltage circuit. When the voltage exceeds
the set range, the parts may be damaged and the input reading may be incorrect. When the system voltage detected by
ECU is too low (below 11V) or too high (above 16V), relevant DTCs shall be generated.

Diagnosis Hint: Check if the diagnostic system is normal.

Check if the charging system is normal.

Perform relevant test for intermittent failure or poor contact.

Terminal ECU

K01

Positive battery terminal +Ra

K03

Positive battery terminal +Rb

K05

Positive battery terminal +Rc

K47

Main relay control

K46

Ignition switch power supply

Power supply of main relay

Main relay

Power supply of ignition switch

Control of main relay

Ignition
switch