Installing Headlight Relays for High-draw Bulbs

The standard harness and switch is adequate for up to 75W for each bulb.  Above that, we recommend that a relay be used to reduce the switch load.  14 gage wires can also be used between the relays and each headlight.

The relays shown are the same type as used for the horn and radiator fan.  Their markings are on the bottom, next to the spade terminals.

Take a power tap off the left side tap of the second fuse.  This has a direct route to the battery, so a fuse or fuses are needed somewhere in the new circuits.  You can fuse in the input wire (violet) or both outputs to the headlight.  The latter method is preferable, so that if you blow one, you will probably still have the other working.

Run separate wires from each relay to each headlight.