answersLogoWhite

0

A tachometer generally has four wires and they are usually hooked up like this: RED = switched hot / power. BLACK = a good metal ground. YELLOW = for the light attached to the cars light harness under dash. GREEN = Trigger, hooked up the the negative on coil or on a GM HEI to the TACH position on the distributor cap.

User Avatar

Wiki User

18y ago

What else can I help you with?