Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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System Description

DESCRIPTION
The fuel pump is driven when the engine is cranking and while the engine is running.

OPERATION
When the engine is cranking and while the engine is running, the engine control module turns the power transistor ON to supply power to the MFI relay coil. This causes the MFI relay switch to turn ON, and current is supplied from the ignition switch via the MFI relay switch to drive the fuel pump.