Several electrical accessories in the vehicle, such as the fuel injection system, horns, starter, and fog lamps use relays to transmit the electrical signal to the component. Relays use a low-current circuit (the control circuit) to open and close a high-current circuit (the power circuit). If the relay is defective, that component will not operate properly. Most relays are mounted in the engine compartment and interior fuse/relay boxes (see illustrations).
i.1a Remove the driver’s dashboard lower cover to expose the under-dash fuse and relay box (on CR-Vs, the under-dash fuse/ relay box is located in the same spot but has an access door in the driver’s dashboard lower cover, so you don’t have to remove the cover)
i.1b on coupes and sedans, the engine compartment fuse/relay box is located on the right side of the engine compartment. The functions and locations of the various fuses and relays are listed on the fuse/relay box cover (on CR-Vs and hatchbacks, this fuse/relay box is located on the left side of the engine compartment