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