AUX Switches - accessories vs amperage

[PRL3]

Just got my new Bronco this week which has the OEM aux switches.

Can I get some advice on what accessories are typically added based on the fuse size?

Ex. What typically gets hooked up to a 30a fuse? Will a 10a handle led ditch lights?

Sponsored

 

[Brian_B]

You are really going to have to look at what you want to hook up. Accessories vary very widely. Even something like lights can vary a lot. A dual LED ditch light could likely go on any of them, but get a 42" light bar and ... maybe you need more amps.

Anything you want to wire up is going to have an amp spec published somewhere.

And, if you use external relays, you can do whatever to where ever. Probably the best bet, because Ford's amp ratings are a bit optimistic if you go look at the actual wire sizes.

 

[brkdncr]

Relays.

 

[Figmo]

Another, loosely related, tip: for LED lighting note that some models support a range of voltages (12v up to 36v). If your lights happen to support this, you can consider adding a step up transformer to convert 12v up to 24v or even 36v.

Why would you want this? Because higher voltage means lower amperage. And lower amperage means higher gauge (thiner) wiring required to support that current.

You'll also get a boost in LED intensity out of the lights.

I have had good success with this running a large number of LED's up to, for example, the roof area. So you don't have to have some big ass cable feeding power to them all. In fact, when I'm designing a new LED lighting solution I will often factor this in and, if I feel it's warranted, I will specifically look for lighting that supports higher than 12v for just this reason.

It does complicate things under the hood a little more in that you'll need a relay to turn on/off your step up transformer. But with a little planning it's not too bad.

 

[RagnarKon]

The 30 Amp fuse is pretty clearly intended for a roof-mounted light bar. The 15 Amp is probably intended for some higher output fog lights or small light bar on the front bumper. And the smaller 10 Amp fuses are probably intended for whatever else.

BUT, you have to be careful. Just taking a look at AUX 1 (30 Amp)... many light bars are actually closer to 40 Amp, and even those that aren't... the wire gauge itself isn't necessarily thick enough to support a 30 Amp load over a distance greater than a few feet. And for that reason a lot of people just use the Aux switches to power relays.

Sponsored