TOPIC: HOOKING UP A TACHOMETER

By Eric (Intenseimages)

There have been several requests wanting to know the proper wiring hookup for a tachometer in our trucks. So, I decided to type up the info and include it in the site FAQ section.

Proper wiring for almost all aftermarket tachometers is as follows:

Red Wire: This wire goes to a constant power source. There is usually at least one extra open space in our fuse panels listed as POWER. This is my preferred area to connect this wire. However, any constant 12 volt power source may be used for this wire

White Wire: This wire needs to be hooked up to a switched power(only has power with key on) source. This wire is usually for the light inside of the tachometer. My prefered location to hook this is to is either in the headlight wiring circuit or to the headlight fuse in the fuse panel. This allows you to have the tachometer light come on when the headlights are turned on

Green Wire: This wire is the ignition firing pulse wire. This wire needs to be hooked up to the - (NEGATIVE) side of the coil

Black Wire: This wire is, of course, the ground wire for the tachometer. This wire needs hooked up to a GOOD ground source on the vehicle.

One other thing ot remember when hooking up your tachometer. Most aftermarket tachometers are designed to work with any vehicle. This means that there is usually a switch located on the back of the tachometer marked 4-6-8.

These numbers are to indicate number of cylinders in the vehicle. Therefore, if you have a 4-cylinder, set switch to the number 4 position, 6-cylinder, set switch to number 6 position, 8-cylinder, set it at the number 8 position.

As for mounting the tachometer, it is mainly up to user preference. Most aftermarket tachometers come with a couple of different mounting options. Some have a bracket that has the tachometer inset in bracket. Almost all of them come with an L-shaped bracket that can moount either flat on the dash or is slightly rounded so that you may use a large hose clamp and secure it to your steering column. Also, alot of the 3-inch and smaller tachometer's may be mounted inset in the dash if you have available space. Mounting them is mainly up to you and where you find it convenient.

I hope this helps clarify this setup a bit

I did a write-up when I put a Tach in my 88 RC and posted it on another site.

Here is a link to that write-up:

http://www.traildamage.net/forum/index.php?topic=71.0

Very easy to install, biggest snag I ran into was deciding where to locate it.