Engine JAC HFC4DA1-2C. Instruction - page 40
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
Maintenance manual for sunray hfc4da1-2c china-IV diesel engines
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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.
Maintenance manual for sunray hfc4da1-2c china-IV diesel engines
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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
Maintenance manual for sunray hfc4da1-2c china-IV diesel engines
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Fault Tree:
Check the battery voltage at
igniting.
Battery fault
Charge the battery.
Check the battery connection.
Fault of battery connectors
Repair accordingly.
Repair accordingly.
Check the ECU connector.
Connector fault
Check the resistance between chassis
and ECU ground.
Adjust the ECU ground.
Is the resistance too high?
Check the charging circuit of battery.
Fault of charging circuit
Repair accordingly.
Get the Technical Support.