Page 814 - Workshop Manual - Tunland (2017)

04-128 DIAGNOSTICS - ENGINE CONTROL SYSTEM

04
P451，P452-INJECTOR METERING OIL RAIL 1 PRESSURE
SENSOR FAULT
P451-FUEL INJECTOR METERING OIL RAIL 1 PRESSURE

SENSOR CIRCUIT -VOLTAGE IS ABOVE NORMAL OR SHORTED
TO HIGH VOLTAGE POWER SUPPLY
P452-FUEL INJECTOR METERING OIL RAIL 1 PRESSURE

SENSOR CIRCUIT -VOLTAGE IS BELOW NORMAL OR SHORTED
TO LOW VOLTAGE POWER SUPPLY

Description
1 . The oil transportation pressure sensor responds to changes of the fuel rail
pressure.The oil transportation pressure sensor has a 5V power circuit, a sensor
signal voltage circuit and a loop circuit.The engine control module (ECM) uses
a common sensor power circuit to provide a 5 volt power supply to the fuel rail
pressure sensor.The ECM also provides a ground to the sensor circuit.The fuel
oil rail pressure sensor provides a signal to the ECM through the fuel rail pressure
sensor signal circuit.The signal voltage will vary according to the pressure of
the fuel oil rail.When the fuel rail pressure is high, the ECM detects a low signal
voltage. When the fuel rail pressure is low, the ECM detects the high signal
voltage.

Circuit Diagram