7 pin power and ground wires gauge factory Tow Package DC to DC Charger

[MaineExplorer]

Hi Folks, my first post! I am trying to figure out what gauge wire is used on the 7 pin trailer outlet on my 2022 Gladiator for the charger and ground leads, it has the regular factory tow package. Everyone talks about adding 6 gauge or lower wire with a separate Anderson connector to a trailer DC to DC charger. I want to install a modest 30 amp solar-DC to DC charger that I would limit the Gladiator alternator draw to 15 amps. When looking at a wire size calculator, I can go 30’ with a max 5% voltage drop and 10 gauge wire is good. I would prefer to use the OEM wire not to void the warranty. I just need to know the gauge of the existing wire and it’s not easy to measure stranded wire. Any advice or thoughts? Is it 10 gauge or lower?

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[Shamus]

I personally would not have a 15A dc-dc charger powered through the Aux power pin on the 7way. Even if your wire spec is correct, that assumes a direct connection between the source, Jeep fuse block, and the load, DC-DC charger, which is not the case as you are going through the 7pin connector. Using the Jeep wiring harness leaves too many unknowns in that you don't know if the aux power has another connection, besides the 7pin, in the dash where the brake controller gets connected. You also don't know if jeep used true 10ga or something smaller but close enough and cheaper.

I did what others have done and ran a dedicated power cable. I have an ARB twin in the bed and have a 30A circuit for the trailer. I used chassis ground so I did not have to run another ground cable back to the battery.

Is it worth the risk of having issues down the road? If you did have issue it may be hard to convince the dealer that the issue with the trailer wiring harness is Jeep's fault.

Take your time and do it right. Run a dedicated line fused correctly. Protect yourself from the penny pinching bean counters at Jeep cutting corners. Just look at the diesel owners issue with the front suspension bottoming out from the factory.

 

[sharpsicle]

I'm not sure I agree with all the "risk" of using the 7-pin wire to charge. It's an always-hot connection. It's powered from the fuse box. Braking systems use different wires. It's a very straight forward connection. I use it for a battery maintainer connection and as an aux power source to plug into no problem, so you'd be fine using it here in principle. The gauge of the wiring is not great, though, so it may not work for your amount of amperage.

The real trouble, though, is the run of the cabling. You're going to lose a lot of the efficiency that the solar panel will give you by having it run back through all that wire on the truck and with it being a not-so-ideal gauge. It's not taking the most efficient path to the fuse box. It meanders around as it makes its way from one end to the other. It's not such a big deal for a low-amperage trickle charger or small accessory like I use it for, but it will come more into play for your application. Ideal solution would be to mount the panel where it can have the least amount of cable going to the battery, and run that cabling as direct as possible. So even though the 7-pin will likely be just fine on paper, in practice you're probably sacrificing more than you realize.

That brings up an important question. Where are you going to be mounting this solar panel? And what's going on that the alternator needs help?

 

[MaineExplorer]

Thanks for the feedback. I think having a dedicated 6awg fused wire to the battery is definitely the right way to go for the long term. The battery and dual input controller would be located in the trailer. I’ve read that the always hot power terminal on the 7 pin receptacle doesn’t provide much more than a maintenance charge amperage. I need to measure the current with the stock lead acid trailer battery that is 50% depleted. I want to get a lithium 100AH battery. I’ve read that it can pull very high current if severely depleted. The DC to DC charger also regulates the max draw. I also will go with modest Solar too that is on the trailer. I’m hesitant to go too deep on a full boondock set up because I have land with power. I’m just getting started on camping without any hookups, more of a trial. I could always experiment with the gladiator alternator current with a 20amp inline fuse which is lower than the factory 30amp fuse. It’s just surprising that with a 240 amp alternator it’s not set up to deliver some decent power to the trailer. Anyone have a lithium battery in their trailer and just using the stock 7 pin as is? Any problems? How many AHs do you charge up while driving half a day or so? Thank you

 

[mx5red]

Pretty sure the 7 pin is fused for 30A, and pretty sure I’ve read on here the wire used is like 16g. Sounds like in practice people don’t see anywhere near 30a but maybe half to a third of that. Doesn’t sound like the factory wire is up for it.

 

[Beemer533]

I personally would not have a 15A dc-dc charger powered through the Aux power pin on the 7way. Even if your wire spec is correct, that assumes a direct connection between the source, Jeep fuse block, and the load, DC-DC charger, which is not the case as you are going through the 7pin connector. Using the Jeep wiring harness leaves too many unknowns in that you don't know if the aux power has another connection, besides the 7pin, in the dash where the brake controller gets connected. You also don't know if jeep used true 10ga or something smaller but close enough and cheaper.

I did what others have done and ran a dedicated power cable. I have an ARB twin in the bed and have a 30A circuit for the trailer. I used chassis ground so I did not have to run another ground cable back to the battery.

Is it worth the risk of having issues down the road? If you did have issue it may be hard to convince the dealer that the issue with the trailer wiring harness is Jeep's fault.

Take your time and do it right. Run a dedicated line fused correctly. Protect yourself from the penny pinching bean counters at Jeep cutting corners. Just look at the diesel owners issue with the front suspension bottoming out from the factory.

This exactly what this connection in the 7 pin is for though, there is no danger here.

Yes, it's not as good as running a 6awg, but it's not going to hurt anything as long as you stay within the limitations. I'd say you could probably use a 15a charger anyway.

In the jeep manual this connection on the 7 pin is literally labeled "battery", so there is really no issue using as a direct connection to the battery (via the 30a Fuse in the PDC).

Are you going to get 30a out of it? No. Should you hook up a 1000w inverter to it? No.

 

[Beemer533]

Hi Folks, my first post! I am trying to figure out what gauge wire is used on the 7 pin trailer outlet on my 2022 Gladiator for the charger and ground leads, it has the regular factory tow package. Everyone talks about adding 6 gauge or lower wire with a separate Anderson connector to a trailer DC to DC charger. I want to install a modest 30 amp solar-DC to DC charger that I would limit the Gladiator alternator draw to 15 amps. When looking at a wire size calculator, I can go 30’ with a max 5% voltage drop and 10 gauge wire is good. I would prefer to use the OEM wire not to void the warranty. I just need to know the gauge of the existing wire and it’s not easy to measure stranded wire. Any advice or thoughts? Is it 10 gauge or lower?

Assuming you are planning on putting the battery and DC to DC charger on the trailer, as long as you stick with probably a 15a charger at most and aren't trying to use a 30 or 50a charger I don't see any issues, this is what that connection is for.

Keep in mind of course that it will take a long time to charge a 100ah battery, unless you have good solar.

 

[MaineExplorer]

My latest thinking is to have two trailer batteries, a 100 AH lithium that gets charged by solar and the converter when plugged in to AC shore power. The existing 40 AH will get charged by the gladiator or converter with an A-B battery switch between the two. I measured the current from the gladiator on a half drained deep cycle battery, it was around 6-8 amps. I actually had an amp clamp data logger but it didn’t record the data which is irritating. After it was pretty well charged, I checked again and it was only 2 amps. My guess is that if the voltage were like 80 percent drained it might go at a decent clip. So I might get 10 to 15 amps from the gladiator for a few hours if I have a low battery which would be great. I wouldn’t need to deal with the DC to DC charger or have concerns about voiding the warranty. I’ll test again when I can drain a battery pretty low.

 

[bd100]

Just curious, what are you running which requires all this battery power? Many/most RV fridges, stoves, water heaters, furnaces and such can run propane. A fan works when air conditioning is not available.

 

[MaineExplorer]

The. 40AH came with the new trailer but I don’t think that is enough, so if I get a new 100 AH lithium iron phosphate it will be much better. Why not have both! The refrigerator is the largest load, it is all electric. Lights, fans, water pump, electronics, so if I’m drawing 5 amps on average that’s almost 100 amp hours per day. Rainy days will be a concern, so a little back up helps. Moving from site to site, that is where the gladiator charging comes in.

 

[ShadowsPapa]

Remember that different battery technologies require different charging rates, voltages, etc.
You don't typically run AGM and lithium on the same circuit and charge them the same way unless the lithium battery comes with its own adaptive electronics. You may over-charge one and under-charge the other.
As long as you charge one, and then use a DC-DC charger to do the other, you'd be ok, but don't link them together directly.

In the jeep manual this connection on the 7 pin is literally labeled "battery", so there is really no issue using as a direct connection to the battery (via the 30a Fuse in the PDC).

Are you going to get 30a out of it? No.

Yeah, going back to - well, almost forever, that connection is to charge or maintain a "camper battery". It's fused 30 so that means the wiring is going to max out at about 30 amps.
25 amps would be fine.


Fuses protect wire and nothing else. The whole point of a fuse is to kill current if the current hits the capacity of the wire. It protects the wire. So they are figuring the max that wire can handle is 30 amps - MAX. Keep any load below that.

People forget that alternators are not indented to be battery chargers.
They are to maintain the battery and carry the electric load of the vehicle they are in.
So don't drain batteries and then assume "the alternator will charge it". That's way less than ideal, and not the purpose of the alternator.
AGM batteries require multiple phases of charging and an alternator just doesn't do that. Lithium batteries like others, but maybe worse, require a lot more to top off that final 10-15%. It takes a very long time to push that final few percent in. It's why PHEVs like the 4xe are programmed to operate as they do.
None of this is like it was years ago where you pop on a fixed voltage charger and it will be fine.

 

[HooliganActual]

I also will go with modest Solar too that is on the trailer. I’m hesitant to go too deep on a full boondock set up because I have land with power. I

As I guy that is running solar on his rig, I have to say that you are only $150 away from full solar based on what you are planning to do. You are already talking about swapping out for a 100aH LiFePO4 battery and using a 15A DC-DC Charger. For $150, you could buy a Renogy 100W 12V Flexible Monocrystalline Solar Panel and you'd be done. Mind you I'm calling out the Renogy panel because that's what I know, there are other options.

I run that panel, a 30A DC-DC MPPT (which can take current and send current to the starter battery/alternator) and 100aH LiFePO4 battery. I'm running a Dometic CFX3 55 fridge and lighting and USB charging and such and have had no issues with running low on power over a weekend or even a week. In fact, on our last 10 day outing, my battery never dropped below 80% SOC.

I know this all has nothing to do with your actual question but, brother, you are right there. By the time you spend the time and money to adapt what you are talking about doing, you could add the solar panel and be done with it, lol.

Cheers

EDIT: Renogy is having a sale right now (again, not sponsored or affiliated with them) and for $159 you get the 30A DC-DC MPPT and the solar panel and wiring kit. If you pick their 100aH Smart battery ($570) and the BT2 module ($40) you can monitor and control the whole thing from a phone app. I don't know what battery and charge controller you were considering but this setup might be competitive with what you were planning to spend...AND...now you'll have full solar.

 

[Beemer533]

.

I run that panel, a 30A DC-DC MPPT (which can take current and send current to the starter battery/alternator) and 100aH LiFePO4 battery. I'm running a Dometic CFX3 55 fridge and lighting and USB charging and such and have had no issues with running low on power over a weekend or even a week. In fact, on our last 10 day outing, my battery never dropped below 80% SOC.

I know this all has nothing to do with your actual question but, brother, you are right there. By the time you spend the time and money to adapt what you are talking about doing, you could add the solar panel and be done with it, lol.

Cheers

EDIT: Renogy is having a sale right now (again, not sponsored or affiliated with them) and for $159 you get the 30A DC-DC MPPT and the solar panel and wiring kit. If you pick their 100aH Smart battery ($570) and the BT2 module ($40) you can monitor and control the whole thing from a phone app. I don't know what battery and charge controller you were considering but this setup might be competitive with what you were planning to spend...AND...now you'll have full solar.

This is essentially my setup as well, the only difference is that I'm using renogys 50A charger and their 175 watt flexible panel. Works really well.

One thing to note regarding the renogy 100ah lifepo4 battery is that they have 2 versions (well 3 if you include the self heating one):

One version is the Bluetooth version but is only rated 2000 charge cycles. You will want the non BT version that is rated for 4000 cycles.

It does have the rs485 port so you can use the BT2 adapter with it.

I actually just bought one on ebay new for $430..

Amazon did have it for $570 for quite a while, but it looks like it's back up the $899 msrp in most places.

 

[MaineExplorer]

Some really great feedback. I’m definitely going to add solar, but I’m leaning against a joint solar MPPT/DC to DC product because the draw on the gladiator wiring will be too high and I would rather not add wiring on a new truck. The two different batteries will be isolated with a three way switch Off, A and B. It’s slightly more complicated because if I just add a three way switch, I can’t get solar and alternator charging at the same time. I can add a second A B switch on the solar feed but it’s not idiot proof, or avoids operator error. If I just isolate the two batteries with the 3 way switch, the demand or gladiator disconnected mode is fine. The converter is smart and adapts to whatever battery it sees, and I’m pretty sure the solar controller will be fine or shutoff when it sees converter power, I need to verify that. When I haul, I can just set it up to the non-lithium battery and the alternator should be fine. The trick is to have the solar charge the lithium battery while I’m hauling so it needs a second switch or a bypass but I can’t forget to put the switch in the correct position. Some kind of double switch would be good. I’ll update my sketch and post later. Thanks for all the feedback.

 

[Flexin]

If you want to skip the guess work, here is the one I have had and used since 2019. Works great and charges the truck while towing. Helpful since I also use a break controller.

https://www.cooltechllc.com/2018-je...harness-kit.html#/69-jl_tow_harness_kit-basic

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