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

Integrated Relay Control Module (IRCM):

The power relay supplies voltage to the Electronic Control Assembly (ECA) when the ignition key is in the ON position. The relay also provides reverse polarity protection by using either internal or external series diodes.
The power relay is contained in the Integrated Relay Control Module (IRCM). The IRCM also contains the fuel pump relay, and the cooling fan relay.