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


PURPOSE
The "EFI Main" relay serves as a source of battery power for several components including the circuit opening relay, (which powers the fuel pump), and the Engine Control Module (ECM).

OPERATION

ECM Main Power Circuit:




The main relay is energized by a signal from the ignition switch. It then supplies battery current from the "EFI" fuse to the ECM and other components.