A tachometer is a gauge on a vehicle that displays the rotations per minute of the engine. Most vehicles are equipped with analog tachometers, however some do not have tachometers at all. Digital tachometers are more accurate than analog tachometers, so they are desired by many enthusiasts. The specific steps to install a digital tachometer will vary depending on your vehicles manufacturer and model, however the general principles are the same.
Disconnect the negative terminal of your battery by unscrewing the negative terminal from the negative battery post.
Locate a suitable area in your dashboard to install your tachometer. Do not choose a location that will impede your driving. Do not choose a location that will be hit with direct sunlight, as this will reduce visibility.
Secure the tachometer to your dash using the drilling template that is provided. Mount the tachometer with the provided screws.
Connect the 100-400 V power and signal inputs to the appropriate terminals on the rear of the tachometer if you are using an electrical signal input. Screw both the positive and negative wires into place. Remember to run all wiring at least 12 inches away from other wires carrying major loads.
Connect the 3 -- 20 V peak magnetic pickup power and signal input into the appropriate terminals on the back of the tachometer if you are using magnetic signal inputs.
Connect the positive and negative outputs on your tachometer to the positive and negative terminals of your over-speed switch.
Reconnect the negative terminal of your battery.
