EFI Main Relay (Prius)
WARNING: This page does not describe the selected car, but rather 11 other vehicles, including the 2003 Toyota Tacoma, 2003 Toyota RAV4, 2003 Toyota Prius, 2003 Toyota Matrix, and 2003 Toyota MR2. However, it is still accessible from the selected car via links, so may be relevant.
EFI main relay may also be referred to as EFI relay. EFI fuse supplies constant battery voltage to one side of EFI main relay. EFI main relay is energized by MREL terminal of Engine Control Module (ECM). When EFI main relay is energized, EFI main relay provides battery voltage to circuit opening relay, +B terminal of ECM and various other electrical components. For EFI main relay location, see EFI MAIN RELAY LOCATION table.