Engine JAC HFC4DA1-2C. Instruction - page 40

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

159

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

160

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

161

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

162

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.

Рассказать друзьям