Fuel Pump Control System

Description
- The powertrain control module engine (PCME) turns the fuel pump ON/OFF via the fuel pump relay. By controlling the fuel pump relay (speed), the PCME also controls fuel pump operation in two phases to improve fuel pump reliability and ensure the necessary fuel amount.

Fuel Pump Relay
- The fuel pump relay is controlled by the PCME and turns the fuel pump ON/OFF.

Fuel Pump Relay (speed)
- The fuel pump relay (speed) is controlled by the PCME and controls fuel pump operation voltage via the fuel pump resistor.

Fuel Pump Resister
- The fuel pump resister controls fuel pump operation voltage. During low-speed engine operation, fuel pump voltage is supplied via the fuel pump resistor.

Operation
(1) In low-speed range (1K terminal of PCME is battery positive voltage).
- The fuel pump is driven by voltage from the fuel pump resister.
(2) In high-speed range (1K terminal of PCME is O Volts).
- The fuel pump is driven by battery positive voltage.

Operating Conditions
The system operates when either of the following conditions is met.
- During engine start-up.
- Solenoid valve (pressure regulator control) operating.
- High speed and heavy load.