Are the Factory Aux Switched grounded?

RubiSc0tt

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Ok, so I used the search and couldn’t find a direct answer. If I’ve missed it, please direct me to the thread.

Please excuse my ignoranceStupid question: Are the Factory Aux Switched grounded? I know they have fuses (two 40amp, two 15 amp) but does this mean they’re grounded, as in- I only have to run a power wire to whatever I am connecting?
And, if that is the case- what do I do with the ground on the device end (lights, compressor, etc)?

likewise, where are you factory Aux switch guys putting your ground wires?

Working on a couple projects in the back of the Jeep (reverse lights and a power hook up for a 30amp compressor) and I’m getting ready to start running wires, but as I was reading I realized I don’t know if I have any good places to ground to- so I should probably check and see what others are doing.

thanks in advance as electrical is not my forte. In the past the most complex things I’ve handled is adding extra lights, and wiring a CB- both of which just went straight to the panel and grounded on some random TJ bolt.

 

Terpsmandan

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That’s what I did when I wired up my winch disconnected. Used aux 3 and wired the ground to the chassis.
 

Fudster

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Ok, so I used the search and couldn’t find a direct answer. If I’ve missed it, please direct me to the thread.

Please excuse my ignoranceStupid question: Are the Factory Aux Switched grounded?

Yes, when properly installed the factory aux swiches share a single ground wire that attaches to the grounding point on the front passenger's quarter panel under the hood as per here:


There is a cable from the factory that leads from this junction point back to the battery's ground or, if you will, negative terminal, completing the circuit: a necessary thing for an appliance to work.

I know they have fuses (two 40amp, two 15 amp) but does this mean they’re grounded, as in- I only have to run a power wire to whatever I am connecting?
All appliances need grounding to work. This completes the circuit. However, a dedicated grounding wire often isn't needed. See below.

Fuses and grounding are separate things. In order to power an appliance you will need to attach one of its two wires to one of the wires shown in this video, for the appropriate aux switch, and the other wire to some grounding point on the vehicle, ideally the place shown in the first video I linked, or the negative terminal of the main battery, or unpainted metal on the vehicle's body.

Fuses exist to protect the wires from melting and/or starting a fire if more power is demanded of an appliance than the wires are rated for.

Many vehicle appliances ground to the body metal, allowing the vehicle to serve as its own ground and to save on cable. That metal ultimately finds its way back to the grounding point on the front passenger's quarter panel, and from there back to battery's negative terminal or, if you will ground.

And, if that is the case- what do I do with the ground on the device end (lights, compressor, etc)?
As mentioned, connect it to the grounding point on the front passenger's quarter panel under the hood, or the negative terminal of the [main] battery or an exposed (non-painted) metal point on the vehicle.

likewise, where are you factory Aux switch guys putting your ground wires?

Working on a couple projects in the back of the Jeep (reverse lights and a power hook up for a 30amp compressor) and I’m getting ready to start running wires, but as I was reading I realized I don’t know if I have any good places to ground to- so I should probably check and see what others are doing.
When working in the rear of the vehicle, distal from the battery, many people ground to some non-painted surface on the vehicle. For example


thanks in advance as electrical is not my forte. In the past the most complex things I’ve handled is adding extra lights, and wiring a CB- both of which just went straight to the panel and grounded on some random TJ bolt.
 

bjm00se

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The only thing I'd add to the excellent info above, is that it does depend a bit on *what* you're installing.

If you're installing sound equipment - head unit, amplifiers, or two way radios, these can be subject to noise interference caused by "ground loops" so for these types of devices, I tend to run a dedicated black ground wire of the same gauge as the power supply line back to the battery central grounding point.

For everything else, as all other said, run the ground to the closest good (non painted) chassis attachment point.

 

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