B Series Truck 4WD L4-2606cc 2.6L SOHC (1992)
Main Relay (Computer/Fuel System): Description and Operation
The Main Relay (also referred to as Fuel Injection or EGI Relay), located in the right front corner of the engine compartment near the battery, supplies
power to the ECU and a number of ECU controlled devices when the ignition is switched "ON", including the circuit opening relay, fuel injectors and a
variety of solenoid valves.
The ECU energizes these devices when needed by completing the circuit to ground.