75 pickup, low voltage at accessory wires?

[tee jay]

Adding some accessories in the cab of my 75 pickup. I found three factory wires under the drivers side dash that are switched accessories but the problem is they dont have a full 12 volts ,dim test light, and whatever you hook to them doesnt work right or not at all. Everything else in the cab has full voltage. Could this be a bad ignition switch or not the right wires? What would they be for if not? All ground wires have been either replaced or cleaned. Truck starts and runs so I guess the steering column is grounded?

 

[Michael Mayben]

Please post the circuit numbers which should appear somewhere on those individual wire runs. I'll compare to the electrical schematic and advise.

I'm converting the entire electrical schematic to a .pdf right now, but it May be too large to actually post to the forum. It's 13 pages! It will be posted later today if the system can handle it.

 

[MarkO]

You May need to check the circuit with a volt meter.

If it comes up around 8 volts you May have found a circuit that goes to the ignition that is stepped down.