I am in the process of replacing my original console gauges in my '69 Z11 with a repro set. None of the original electric gauges were functioning.
I got started by assembling the new gauge set into the new pod, using the originals as a model. The original set had a ground wire attached to the base of the rear mounting plate and the other end attached to the top of the front mounting plate - I used the same wire in the new gauges the same way. The only other variation was a flat piece of wound small wire on the back of the original fuel gauge, I attached this to the new fuel gauge.
All the new gauges were wired as follows:
Fuel - double pink and brown wire plug, small green wire to one terminal, small red wire to one terminal, black ground wire and small black wire to the other terminal.
Volt - black/white and black wire plug.
Temp - green and pink wire plug, some sort of ceramic piece connecting the other terminals, This may be incorrectly installed. Is this supposed to be covered by the plastic piece between the two other terminals, because it appears that the plug terminals are touching the ceramic piece?
Anyway, here is what happened.
With the gauges in the pod, I connected the harness plug. The 4 small lights came on without the key or the light switch on.
I figured that the ground wire needed to be attached to the shifter plate location.
As I was attempting to attach the wire is sparked. I detached the positive cable on the battery, then attached the harness ground wire.
When I reattached the battery cable guess what? Yep, it fried the two black ground wires in a nice mushroom cloud of smoke.
It didn't damage any other wires, and none of the gauges seem to have been affected.
Where have I gone wrong with this?
'69 Z11 Pace Car, 350/4 speed