rail psi wiring question

[Mobius1]

On the gauge wiring harness, (the harness that has the dimmer control on it) there are 3 wires, a red, white and gray. The white ties into the dimmer wire behind the headlight switch, the grey is ground, what is the red wire for?



TIA

 

[Triton]

that should be your hot wire to the ignition.

 

[Mobius1]

that should be your hot wire to the ignition.

So that would be a switched power source?