Replacing tractor lights can be as simple as changing the light bulb or, if the lights are being upgraded, the task may involve removing the old lights and mounting new ones, and running new wires from the battery to the lights. If the old lights are broken and new lights of the same voltage are available, the new lights can usually be installed using the factory wiring.
To replace a light bulb on a tractor, remove the bulb from the rear of the light by twisting the bulb's base a quarter-turn counter-clockwise and pulling gently. Pull the old bulb out and replace it with a new one, and reinstall the bulb assembly to the light cover. Replace incandescent light bulbs with halogen bulbs, if possible, to increase visibility.
Many modern farmers are upgrading to LED lights for their lighting and energy-saving capabilities, longevity and low cost. If this installation involves replacing the light housing and mounts, most LED light kits include mounting hardware, wiring and instructions. After the old light assembly is removed, you may need to drill new holes in the tractor's body in order to properly mount the new assembly.
If the factory wiring cannot be used for the new lights, run two wires from the lights to the light switch, which is usually located near the distributor. The best way to run the wires is to follow the path of the factory wiring, using an insulating plastic cover if necessary. Confirm that the positive and negative wires are connected to the appropriate terminals on the switch. Consult the tractor's owner's manual or maintenance guide, if necessary.