Can anyone tell me in idiot speak how to hook up a tacho??
I have no diagrams, charts, etc, as the tacho was in an old car and then pulled out.
The only problem i can see is telling which wire is for what from the tacho itself.
Its a cheap universal unit for 4, 6, or 8cyl cars...

there should only be 3 wires
red---positive
black---earth
and another which goes to the negative side of your coil
there may also be wires if it has a light which are simply positive and negative.
just hook the tacho positive to a positive which has power from when your ignition lights come on and the earth is self explanatory.
if you dont already have a wire from the front to the back try running a harness through the roof( that is where the interior light is)

if it helps - wire that goes to the distributor side of the coil is usually green
& to the dash lights for illumination is usually white, this is the case on most Asian made tachos
so
red - ignition - powers the thing
black- earth
green-(generally) takes the ignition pulse to calibrate the signal

white (generally) just lights it up at night

On the Tacho in the Kombi There were four wires.
Red +
Black -
White (coil -ve)
Blue (light)

The one for the light was easy to distinguish as it went directly into a little bulb holder clipped in the back.

on mine it goes

red- battery +ve
black- ground
green- coil +ve terminal
white- speedo light terminal on fuse box(check the fuse box diagram in a car manual for your car)

The wire colours can vary with different brands...

Ah - sounds very straight forward.
Thanks one and all!

Im hooking up a VDO tacho one of the old back light one's, there are some jumper switch's on the back 1-5 it say's on the fitting instructions to celect 2 for a four cylinder motor, should the button be up with all others down, or down with all others up, to be selected over the top of the switch's it says OPEN.

Rob....

[Edited on 1-6-2003 by Robo]