Tachometers work by counting pulses generated by the ignition system, alternator, tach signal generator or magnetic pickup sender. The tach is hooked up to +12VDC, Ground. By selecting the right tach and setting the switch on the back to the correct position you let the tachometer know how many pulses are sent per each engine revolution. These tachometers have a warning light system built into the dial that show off warning indicators when a fault is detected from the engine.
No Oil Warning
Engine Overheat Warning
Check Engine Warning
Low Oil Warning
Designed for quick and simple installation