Aux Switch Fuses Blowing

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KG885

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Hi Guys, I just picked up my 2025 R and am in the process of hooking up some lights. I have the BD ditch lights setup on Aux 2 and the work great (transferred from my 2023 37 package).

I bought a set of HF Roadshock Edge 6s for the front bumper. I also bought the HF harness, which has a built-in relay. When I hooked (tested) them up to the HF switch, the highs, lows, and amber running lights all work great.

I cut the HF 2-way switch off of and wired the amber running lights to AUX 6, and they work fine. I also ran the lead for the low beams to AUX 3 (15A) and they work fine. I have tried hooking the trigger wire from the relay to AUX 5 and it will blow if I have more than one light hooked up at a time.

I am by no means an expert, but I was under the impression that the load was handled by the relay and the the switch itself only serves as a signal to turn on the relay. I have double checked everything. The wires are all tight and the truck has yet to go on the road with the lights hooked up. I have not run the high and low beams at the same time, and both lights still work as they should when I back test them with the HF switch. Does this make any sense? The relay is a 40A. I know that the AUX switches only go up to 15A. Any thoughts?

Is the issue just that the 5A Aux switches aren't enough to run the relay?

Thanks, in advance!
 
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Nex

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You are overloading the circuit. Is the harness you have run straight to the battery?

You need the uplifter switch to power the relay in order to power on the lights. Otherwise you are having the Ford harness power the lights, which is over the load rating.

Pictures would really help us help you here.
 
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KG885

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Thanks for the quick reply! I was going to amend the original post after looking once more at the setup. I am able to run both of the lights (on either high or low beam when using AUX 3 (15A). The trouble comes when trying to use the lower amperage AUX switches (#5 or #6 which are both 5A).

You are correct, with wires have a 30A fuse going direct to the battery and also grounded at the ground point next to the batter (near the RF fender). The wire with the 30A from the battery goes to the relay and then to the lights. The AUX switches also go the relay.

Here is the harness I am using. I am using the white/blk wire for the high beam trigger and the red/blk for the lows.

https://www.harborfreight.com/off-road-light-wiring-harness-59105.html
 
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The Car Stereo Company

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the relay requires 200ma max to work. definitely not enough to cause switch overload. something else is wrong with your wiring
 
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