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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Main Relay (Computer/Fuel System): Description and Operation

DESCRIPTION AND OPERATION
While the ignition switch is ON, battery power is supplied to the engine control module, the injector, etc.

When the ignition switch is turned ON, current flows from the ignition switch through the MFI relay coil to ground. This turns ON the MFI relay switch and power is supplied from the battery through the MFI relay switch to the engine control module.