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", including the crank angle sensor, fuel injectors and a variety of solenoid valves.
The ECU energizes these devices when needed by completing the circuit to ground.