No power to gauges, no headlights, no speedometer, and no reverse lights

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bigboof

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Tate
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hello gentlemen i am new here. i am looking for some help diagnosing some wiring issues. first off i have replaced all the fuses and double checked recently that they are not blown. my gauges and speedo don't work and neither do my headlights, i don't know if it is ground i am lacking or if there is some sort of wiring issue. keep in mind this truck sat on a ranch for 20+ years and i have looked at the wiring behind the instrument cluster and some is not factory and others is. i need help. how do i diagnose where the problem is?
 

Matt69olds

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Get a 12 volt test light, ground it to a known good ground. Verify the light and ground is good before going any further.

Turn on the ignition, check for power on both sides of the gauges fuse. No power, or power on only one side of the fuse will determine the next step.

Do the taillights work? If so, the headlight switch has power. That means the fusible link under the hood isn’t blown.

Does the high beam indicator in the dash work? If so, you know the headlight switch, dimmer switch, and related wiring is good, check the headlights. You might have a bunch of bulbs out.
 

WP29P4A

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May as well start at the beginning.(with a test light or meter) Does the battery hold a charge? Is the battery fully charged? (12.? volts) Check and clean the battery cables, make sure you have a clean connection for the ground to the engine and to the fender/radiator support. Do you know where your grounds should be? Are they all still attached? Check the fusible links.

I prefer to work from the power source, out towards the device having the problem, to save time. If the voltage isn't making it out of the battery, checking the end where the device is,is not going to help. Since it sat on a farm for 20 years, might want to check for chewed wires under hood and other locations where wiring loom passes through openings in metal panels.

You did good on your list of what doesn't work, fill us in on what does work to help you narrow down the location of the issue.
 

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