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

PURPOSE/OPERATION
While the ignition switch is ON, battery power supply is supplied to the engine control module, injectors, volume air-flow sensor, etc.
Turning the ignition switch to the ON position causes current to flow from the ignition switch through the multiport fuel injection relay coil to ground. This turns the multiport fuel injection relay switch on and supplies power from the battery to the engine control module via the multiport fuel injection relay switch.