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



The Main Relay (also referred to as Fuel Injection or EGI Relay), located in a relay panel at the right rear corner of the engine compartment, supplies power to the ECU and a number of ECU controlled devices when the ignition is switched "ON." These devices include the crank angle sensor, fuel injectors and a variety of solenoid valves. The ECU completes the circuit by grounding these devices when indicated by its calculations.