Wiring Reverse Lights and Using Auxiliary Switch(es)

[Jeff1759]

Baja Designs S2 Reverse Lights arrived today. I have the Aux Switches. I am a bit confused on the whole amps/watts/fuse size thing.
I'd like to use AUX 2 for reverse lights as it is closer to the driver and I plan on using AUX 1 for future front light bar.
The only info I can find on the BD S2's states they are 24 Watts. I can find nothing mentioned about amps. I'm guessing because they are LED's, they are very low draw.
SO, each aux switch is wired through a specific fuse in the PDC. Aux 5 is a 20A, AUX 1 and 2 are 40A.
With these lights having such a low demand, does it matter if I wire them through a 20A or 40A fuse? Should I replace the fuse of whichever switch I use to work with the 24 Watt lights? If so, what size fuse would that be running 20ft of 12 gauge wire?
Hope this makes sense...

 

[H3LZSN1P3R]

Baja Designs S2 Reverse Lights arrived today. I have the Aux Switches. I am a bit confused on the whole amps/watts/fuse size thing.
I'd like to use AUX 2 for reverse lights as it is closer to the driver and I plan on using AUX 1 for future front light bar.
The only info I can find on the BD S2's states they are 24 Watts. I can find nothing mentioned about amps. I'm guessing because they are LED's, they are very low draw.
SO, each aux switch is wired through a specific fuse in the PDC. Aux 5 is a 20A, AUX 1 and 2 are 40A.
With these lights having such a low demand, does it matter if I wire them through a 20A or 40A fuse? Should I replace the fuse of whichever switch I use to work with the 24 Watt lights? If so, what size fuse would that be running 20ft of 12 gauge wire?
Hope this makes sense...

They would be 1.8A also you have a rear feed built in to the truck for the aux switches you can setup… you can run any switch and swap the fuse

 

[Jeff1759]

They would be 1.8A also you have a rear feed built in to the truck for the aux switches you can setup… you can run any switch and swap the fuse

Thanks for the fuse size!
I’m aware of the feed to the rear and should probably have patience and do it that way. Not terribly psyched on getting at that feed in this cold weather, but yes, patience and do it right…
Thanks for the response!

 

[Brutal_HO]

Thanks for the fuse size!
I’m aware of the feed to the rear and should probably have patience and do it that way. Not terribly psyched on getting at that feed in this cold weather, but yes, patience and do it right…
Thanks for the response!

The front end of that rear feed is available in the cab. There's a jumper included in the upfitter wire bag that has to be used. You can cut/splice the wires in the jumper to bring AUX power to the rear.

For the 21+ you have something like 5 pass-thru circuits between the cab and AUX PDC location. You use one of those connected to an AUX and tie it to the circuit running from the cab to the rear chassis.

AUX pass-thru wiring.

mine is a '19, yes Did you just buy the parts from the dealer, or is there someplace putting together a kit?

hdrams.com

 

[Jeff1759]

Thanks Brutal! This stuff can make my head spin sometimes so I will take it slow.

 

[Jeff1759]

The front end of that rear feed is available in the cab. There's a jumper included in the upfitter wire bag that has to be used. You can cut/splice the wires in the jumper to bring AUX power to the rear.

For the 21+ you have something like 5 pass-thru circuits between the cab and AUX PDC location. You use one of those connected to an AUX and tie it to the circuit running from the cab to the rear chassis.

AUX pass-thru wiring.

mine is a '19, yes Did you just buy the parts from the dealer, or is there someplace putting together a kit?

hdrams.com

Brutal,
Digging into this now.
Ive located the heavier Red/White wire at rear of truck near spare tire.
I've got the correct plug located near parking brake in cab.
I cannot find the Red/White wire (from rear of truck) anywhere in the cab area. Is it a stand alone wire or is it connected to the white female plug near parking brake?
So confusing...

 

[Will_T]

I seem to remember in that other long thread about this that I posted I found that wire was red/white at the rear and another color near the parking brake. I used continuity to figure that out.

 

[Brutal_HO]

Brutal,
Digging into this now.
Ive located the heavier Red/White wire at rear of truck near spare tire.
I've got the correct plug located near parking brake in cab.
I cannot find the Red/White wire (from rear of truck) anywhere in the cab area. Is it a stand alone wire or is it connected to the white female plug near parking brake?
So confusing...

The two wires that run to the rear (IGN, BAT) are on the Grey upfitter jumper D2621A that's up behind the parking brake assembly. There's two pass-thru circuit G425 and W550 (added in 2021) in the same jumper. You can repin to carry those to the back and connect to AUX under the hood.

Dash camera

Anyone done a dash camera install yet? Looking for the switched power to tap into. I'm thinking i'll find some in the mirror or under that massive cover on the windshield. Any tips taking that thing off so I don't snap any plastic clips?

hdrams.com

AUX pass-thru wiring.

mine is a '19, yes Did you just buy the parts from the dealer, or is there someplace putting together a kit?

hdrams.com

 

[Jeff1759]

I think it's starting to sink in. On the schematic I trace back from "F" which I believe is the heavier RD/WH wire at rear of truck, which goes to the connector in cab at emergency brake area.
I plug my 5 pin connector from bag into this. #4 and #3 on this connector are jumped giving me a battery feed to rear of truck.
I then go to light and dark gray connectors under hood, next to PDC and install a jumper from dark gray AUX 2 light gray #4?

 

[Brutal_HO]

I think it's starting to sink in. On the schematic I trace back from "F" which I believe is the heavier RD/WH wire at rear of truck, which goes to the connector in cab at emergency brake area.
I plug my 5 pin connector from bag into this. #4 and #3 on this connector are jumped giving me a battery feed to rear of truck.
I then go to light and dark gray connectors under hood, next to PDC and install a jumper from dark gray AUX 2 light gray #4?

You would not connect either existing IGN or BAT wire directly to an Aux, they already have power.

If you want to use one of those circuits, you would clip the jumper or re-pin the wire to one of the pass thru circuits and then connect that pass-thru circuit to an AUX switch.

 

[Jimmy07]

I think it's starting to sink in. On the schematic I trace back from "F" which I believe is the heavier RD/WH wire at rear of truck, which goes to the connector in cab at emergency brake area.
I plug my 5 pin connector from bag into this. #4 and #3 on this connector are jumped giving me a battery feed to rear of truck.
I then go to light and dark gray connectors under hood, next to PDC and install a jumper from dark gray AUX 2 light gray #4?

This is your route to get the reverse lights on aux switch 2 using the rear red/white wire. On the accessory bag connector with two jumpers, move the jumper from position 3 to position 5. On the two aux connectors at the PDC, jump light gray 4 to dark gray 1.

 

[Jeff1759]

Thanks for the layman’s speak Jimmy.
Had everything wired up after spending a lot of time with it. Reverse lights were on. Constantly. Even without having the acc on or truck started, even with both plugs next to PDC removed.
It was close to getting dark and I was wired out.
Had to cut the power wire I had just soldered up nicely to get the lights to go out.
Rather than pull my hair out or throw something, I made the decision to just run a separate wire back on the next warm day.
I may give your way a go first.

 

[BighornHDRam]

Why couldn't you just run a 14g wire from the Dark Grey Upfitter connector #2 for Aux 2 to the back of the truck and wire the power to the BD lights and then ground it back there as well just like the BD kit does? This is how I plan on doing mine unless I'm wrong on this as these backup lights are only 12W/.9A. I'm just waiting for my last Deutsch connector to come off backorder.

 

[Jimmy07]

Thanks for the layman’s speak Jimmy.
Had everything wired up after spending a lot of time with it. Reverse lights were on. Constantly. Even without having the acc on or truck started, even with both plugs next to PDC removed.
It was close to getting dark and I was wired out.
Had to cut the power wire I had just soldered up nicely to get the lights to go out.
Rather than pull my hair out or throw something, I made the decision to just run a separate wire back on the next warm day.
I may give your way a go first.

If you leave #4 jumped to #3 on the accessory connector (like it comes), then you are feeding the rear red/white wire constant battery power. That’s why you need to move the jumper wire from position #3 to position #5.

 

[Jimmy07]

Why couldn't you just run a 14g wire from the Dark Grey Upfitter connector #2 for Aux 2 to the back of the truck and wire the power to the BD lights and then ground it back there as well just like the BD kit does? This is how I plan on doing mine unless I'm wrong on this as these backup lights are only 12W/.9A. I'm just waiting for my last Deutsch connector to come off backorder.

Because when you have the factory aux switches, there’s no reason to have to run any wire out of the engine bay to the rear of the truck, since wires are already there. It would be a wasted effort.

 

[BighornHDRam]

Because when you have the factory aux switches, there’s no reason to have to run any wire out of the engine bay to the rear of the truck, since wires are already there. It would be a wasted effort.

Alright, when my new 2022 with the Aux switches shows up I will look for the wires out back as my 2019 2500 does not have Aux switches nor the wiring out back.

 

[Jeff1759]

If you leave #4 jumped to #3 on the accessory connector (like it comes), then you are feeding the rear red/white wire constant battery power. That’s why you need to move the jumper wire from position #3 to position #5.

I just needed the addition of your clearly stated instructions to add to what I've learned today. The muddy waters have cleared. Thanks again.

 

[BighornHDRam]

This is your route to get the reverse lights on aux switch 2 using the rear red/white wire. On the accessory bag connector with two jumpers, move the jumper from position 3 to position 5. On the two aux connectors at the PDC, jump light gray 4 to dark gray 1.
View attachment 26663

Looking at your drawing wouldn't you need to have it jump light gray 4 to dark gray 2 to get it to work on Aux 2 switch as he wants it.

You have it going to jump light gray 4 to dark gray 1 for Aux 2 but in the diagram that's Aux 1.

 

[CanadianIronhead]

Also installed through AUX2, love em, especially when someone is tailgating you at night.

 

[Jimmy07]

Looking at your drawing wouldn't you need to have it jump light gray 4 to dark gray 2 to get it to work on Aux 2 switch as he wants it.

You have it going to jump light gray 4 to dark gray 1 for Aux 2 but in the diagram that's Aux 1.

Yes, that’s correct. I got cross eyed when I saw #2 almost meet the #1 90 degree line on the drawing.