Fuel Pump: Description and Operation

Fuel Pump Electrical Circuit - Crank Stage:

Fuel Pump Electrical Circuit - Run Stage:

Purpose
The fuel pump is used to provide a constant supply of high pressure fuel to the fuel injectors.

Operation:
The control relay and the ECM control the fuel pump "ON/OFF" operation.
The fuel pump is activated when the engine is cranked. A crank signal from the starter circuit energizes the circuit opening relay which turns "ON" the fuel pump. Once the engine is started and the key is released, the ECM takes control fuel pump through a second coil in the circuit opening relay. If the ignition system is not working correctly, the fuel pump will not run.

Fuel Pump:

Construction:
The fuel pump main components are:
^ Armature
^ Bearings
^ Brush
^ Casing
^ Check valve
^ Impeller
^ Magnet
^ Relief valve

Location
Mounted in the fuel tank.