Aftermarket tach connection location?

[90Sub]

I have an aftermarket tach mounted on top of the dash, was installed before I bought the rig. I was wondering where those type actually hook up so I can check the connection. It's starting to go out sometimes. Anyone know?

 

[MudTruk]

well, typically there are 4 wires to hook up a tach. I am assuming that you have a "standard" tach. The colors may (can) vary by manufacture. Black is 12V ground. It is always good to check your ground wire. Many problems can be solved by a good ground connection. Usually the red wire goes to the distributor on the Tach electrical lead. This is usually a soderless spade type connection on GM HEI coils. My tach has a constant power lead that is connected to a 12V switched source. And the last wire connects to an instrument panel switched hot lead. This is to provide lighting to the tach when the lights are on. Hope this helps.

Pete

 

[A&P]

I have a sun pro 4 1/2 incher. Goes like this
Black=Ground
Red=12V Source IGN
Green=Dist. Tach Lead
White=Dimmer
Just My $.02

 

[chvyhs]

My AutoMeter is hooked up the same as your SunPro.

 

[Anteak]

What about a S/W 0 - 8,000 tach????
There are only three wires;

Black
White
Red

The green wire doesn't exist.

73 Blazer, So. Ca.