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

Multiport Fuel Injection Relay:

OPERATION
While the ignition switch is ON battery power is supplied to the engine control module the injector the volume air flow sensor etc.

When the ignition switch is turned ON current flows from the ignition switch through the multiport fuel injection relay coil to ground. This turns "ON" the multiport fuel injection relay switch and power is supplied from the battery through the multiport fuel injection relay switch to the engine control module.