Fuel gauge feed

[jsera]

Gents, in wiring up my new aftermarket gauges (on my 72 with factory dummy gauges) I have had to chop up the factory connector and label it according to the wiring diagram to be able to later match these up with my new gauges.

My question: there are two fuel gauge wires on the factory wiring diagram (pink and brown if I remember right), is one of these (brown) a low fuel warning light?

[72_swb]

pink should be the ohm signal wire from the sending unit. and the tan or brown I think was the power to the gauge.

[jsera]

Originally Posted by 72_swb

pink should be the ohm signal wire from the sending unit. and the tan or brown I think was the power to the gauge.

Is there anything special about this wire, it would just be a 12v ignition switched I could use to power other gauges too?

[72_swb]

Originally Posted by jsera

Is there anything special about this wire, it would just be a 12v ignition switched I could use to power other gauges too?

You really need a decent multi meter. Turn the key on and see if the brown tan wire powers up. If it doesn't turn the headlights on and see if it does. It may be the light for the guage ???? cant remember sorry.

[jsera]

Originally Posted by 72_swb

You really need a decent multi meter. Turn the key on and see if the brown tan wire powers up. If it doesn't turn the headlights on and see if it does. It may be the light for the guage ???? cant remember sorry.

I have a new headlight switch coming in today so hopefully I can figure it out. I was fairly certain the pink was my sender, but having tested the gauge and getting a reading below E I had my doubts. I may have something to do there too...

[VetteVet]

Originally Posted by jsera

I have a new headlight switch coming in today so hopefully I can figure it out. I was fairly certain the pink was my sender, but having tested the gauge and getting a reading below E I had my doubts. I may have something to do there too...

Pink is the power for the dash cluster from the fuse panel including the fuel gauge and the temp gauge and the brown is the sending unit wire from the FUEL terminal on the fuse panel continuing from the sending unit.

do not confuse the tan or brown wires, one comes from the brake warning and the other is the fuel sending unit wire.

[jsera]

Originally Posted by VetteVet

Pink is the power for the dash cluster from the fuse panel including the fuel gauge and the temp gauge and the brown is the sending unit wire from the FUEL terminal on the fuse panel continuing from the sending unit.

do not confuse the tan or brown wires, one comes from the brake warning and the other is the fuel sending unit wire.

Attachment 1617814

Thanks for the help, so if I need to feed power to multiple gauges the pink wire is my go to.

as far as the brake warning that would be for the parking brake I guess but any what the wire to the proportioning valve is for?

[VetteVet]

I wouldn't recommend using that wire for more than you already have. It comes off the fuse panel as the cluster feed wire which is controlled by a 3 amp fuse. If you want to run more gauges you should power them separately or you might start blowing the CF fuse and not know why.

The tan or brown wire is for the prop valve wire, there is no emergency brake (parking brake) warning light until the later model trucks. It turns on the warning light in the dash cluster when the brake pressure between the front and rear brake systems becomes unequal. A switch in the proportioning valve grounds the brown wire and turns on the warning light if the key is on and the engine is running. It should light during starting as a test of the warning bulb.

[jsera]

Originally Posted by VetteVet

I wouldn't recommend using that wire for more than you already have. It comes off the fuse panel as the cluster feed wire which is controlled by a 3 amp fuse. If you want to run more gauges you should power them separately or you might start blowing the CF fuse and not know why.

The tan or brown wire is for the prop valve wire, there is no emergency brake (parking brake) warning light until the later model trucks. It turns on the warning light in the dash cluster when the brake pressure between the front and rear brake systems becomes unequal. A switch in the proportioning valve grounds the brown wire and turns on the warning light if the key is on and the engine is running. It should light during starting as a test of the warning bulb.

Thanks for the info, Id wondered by what sorcery it worked haha