Daihatsu F300 Service Manual page 1372

EFISYSTEM
FUEL SYSTEM
The fuel system is a system which supplies the injectors with fuel necessary for combustion. This system is
composed of the fuel pump, fuel pipes, fuel filter, pressure regulator, fuel delivery pipe and injectors.
Fuel sucked up from the fuel tank by means of the fuel pump is sent under a pressurized condition to the
fuel delivery pipe through the fuel fitter. The pressure regulator mounted at the delivery pipe keeps the fuel
pressure at a value about 250 kPa (2.55
kgf/cm~
higher than the intake manifold inner pressure. Such
difference between the intake manifold inner pressure and the fuel line inner pressure prevents any variation
in the fuel injection rate of each injector.
Any excess fuel returns to the fuel tank through the pressure regulator. This makes it possible for the fuel at
a comparatively low temperature in the fuel tank to be supplied into the fuel line, thus preventing percolation.
The fuel pump is driven by the ECU.
INTAKE SYSTEM
The intake system is a system which supplies air necessary for combustion with each cylinder.
Air sucked from the cool air intake of a comparatively low temperature is sucked into the surge tank through
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the air cleaner, and air chamber depending upon the opening degree of the throttle valve.
Then, the air goes through the intake manifold into each cylinder.
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CONTROL SYSTEM
The control system is a system which controls the fuel amount, using the ECU, by detecting the engine
conditions and vehicle running conditions, based on signals inputted from the various sensors to the ECU.
Fuel pump control (FC)
This system controls the fuel pump operation. This system drives the fuel pump for two seconds when the
ignition key switch is turned ON and/or the ignition signal is inputted. It also drives the fuel pump when the
starter switch is turned ON.
Idle-up VSV control
This is a system which actuates the idle-up VSV when the engine is cold (i.e. the cooling water temperature
is below 70°C) or when heavy electric loads (e.g. heater blower, defogger, headlamps) are applied, thus
maintaining a proper engine revorutional speed.
SELF DIAGNOSIS FUNCTION
If signals inputted from main sensor systems to the ECU do not conform to the specified values memorized
in the ECU, this malfunction is memorized.
(There are some items which are not memorized.)
Since the memorized malfunction code is retained by the back-up power supply from the battery. the code
remains memorized when the ignition key switch is turned OFF.
The memorized malfunction code can be reset by cutting off the power supply to the ECU.
When any malfunction concerned with the important items occurs, the check engine lamp provided inside
the combination meter is turned ON, thereby warning the driver of such malfunction. The check engine lamp
remains illuminated as long as the malfunction concerned with the important item persists. However, if the
encountered maHunction takes place temporarily and the normal state is restored, the check engine lamp
goes out. In this case, however, the malfunction that has once occurred is memorized to the ECU, using the
pertinent code number.
To indicate the malfunction code during the inspection, short the test terminal of the check connector located
at the fender panel right side of the engine compartment with the ground terminal. The check engine lamp
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inside the combination meter flashes as many times as the number of the corresponding malfunction code. •
With the aid of the diagnosis code, the checking operator can perform trouble shooting efficiently. .
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