Ok i got an 84 Trans Am, i have a Speco Tach and i had to hook it to a ignition ON wire for power, i have found a green one that comes out of the steering colum that gets about 12.80V with Ingition ON but when it is OFF i still get .54V will this hurt the tach to have .5 of a volt when it is not used? and dose anyone know what the green wire actualy dose?
It goes to a long/thin plug with about 5+ wires in it, there is also a purple (i think) with 12.80V On Ignition but also .54 when Off.

 

Save your self some trouble and drop your steering colum, find the ignition switch. There is a pink wire there, splice into that that is the ignition on power for your car.

 

Oh just had a look, lol the wire i said i thought was purple is actualy pink.
But im still getting .5v out of that when the ignition is off.
All the wires are under the steering colum, They must have moved them there when it was converted to RHD to make it easer to acess them.