Fuel Pump Control Module (Q45)

When ignition is turned on, engine is cranked or running fuel pump relay is activated. Battery voltage is directed from the fuel pump relay to Fuel Pump Control Module (FPCM) and fuel pump. The FPCM adjusts the voltage supplied to fuel pump according to engine conditions. FPCM supplies about 13 volts to fuel pump under following conditions:

• One second after ignition switch is turned to ON position.
• During engine cranking.
• Thirty seconds after engine starts at temperatures greater than 122°F (50°C).
• Engine temperature is less than 50°F (10°C).
• Engine is running under heavy load condition.

Under conditions other than those listed, FPCM limits fuel pump voltage to about 9.5 volts.