EFI Main Relay (ES300 & RX300)
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2002 Lexus SC 430, 2002 Lexus RX 300, 2002 Lexus LX 470, 2002 Lexus LS 430, and 2002 Lexus IS 300. However, it is still accessible from the selected car via links, so may be relevant.
The EFI fuse supplies constant battery voltage to EFI main relay. Relay is located in fuse/relay box in left side of engine compartment. When EFI main relay is energized, EFI main relay provides battery voltage to circuit opening relay, and various other electrical components. EFI main relay also provides battery voltage to +B terminal of ECM.