Is it safe to run a battery tender through the DC power port?

[ShredAZ]

Merry Christmas everyone! I was gifted a 5a Battery Tender. My original plan was to hardwire it, but then I remembered my 2003 came with an "always hot" DC power port in the cab from the factory.

I believe our power ports use a 20a blade fuse. I figure it's safe to run a 5a battery tender through it as a result.

Can anyone confirm that my plan is good to go?

 

[Chris]

Merry Christmas everyone! I was gifted a 5a Battery Tender. My original plan was to hardwire it, but then I remembered my 2003 came with an "always hot" DC power port in the cab from the factory.

I believe our power ports use a 20a blade fuse. I figure it's safe to run a 5a battery tender through it as a result.

Can anyone confirm that my plan is good to go?

It should be safe, especially since it’s only drawing 5 amps. The fact that the power port is fused at 20 amps provides a good buffer. Just make sure the wiring and connections are in good shape to handle that flow, and keep an eye on it the first few times you use it to ensure everything is working smoothly.

Additionally, if you can, check the specs of the Battery Tender to ensure it doesn’t have any specific requirements regarding the power source.

 

[macleanflood]

I personally prefer to keep any unattended battery chargers as detached from everything else in a vehicle as possible.

I'd hard wire it to the battery with a fused ISO connector and run a pigtail someplace convenient. Under a tire well or just under the hood.

I don't like vehicle fires. I especially don't like vehicle fires that burn down garages, shops and houses.

-Mac

 

[GoldenGorilla]

My other "daily driver" car is an older 911. Not an issue for me since I drive it often. Lots of folks in that community don't daily theirs and many of them use a battery tender plugged into the hidden power port up in the passenger footwell. Many others leave the frunk cracked open. I have never seen an issue among them either way. Hacked up and modified wiring doesn't tend to be a thing in that world.

 

[mjonesjr84]

You'll be better off hooking it directly to the battery as it is intended.

 

[Camdenst]

I'd hard wire it to the battery with a fused ISO connector and run a pigtail someplace convenient. Under a tire well or just under the hood.

Would you go as far as to spice in a fuse to one of those trickle chargers like Battery Tender?

 

[mjonesjr84]

Would you go as far as to spice in a fuse to one of those trickle chargers like Battery Tender?

My NOCO came with a fuse inline.

To expand on what @macleanflood said, here is what I did with mine. I used this AC port so no wire splicing necessary.

https://www.amazon.com/dp/B0CZ3J5F98?tag=wranglerorg-20

 

[5632]

I attach all my tenders (except one) to the alternator and have never had a problem for 30+ years.

 

[CharlesHS]

I attach all my tenders (except one) to the alternator and have never had a problem for 30+ years.

While you may have not had any problems; that connection point would not be my first choice.
I would go direct to the battery or the route macleanflood describes above.

 

[DavidBT]

When I had my hip revision surgery a year ago, I used a 7.5 amp solar charger directly to the power port for at least three months while I recovered. No issues at all.

 

[mrblaine]

I attach all my tenders (except one) to the alternator and have never had a problem for 30+ years.

To clarify, you are attaching to the alternator output power stud that has the cable that goes to the PDC or battery + terminal?

 

[5632]

To clarify, you are attaching to the alternator output power stud that has the cable that goes to the PDC or battery + terminal?

Yes sir.

 

[mrblaine]

Yes sir.

Then it is exactly the same as hooking it up to the battery, the cigar lighter always hot circuit, or any other method that eventually ties it to the battery. You've just used less wire to do it.

 

[5632]

Then it is exactly the same as hooking it up to the battery, the cigar lighter always hot circuit, or any other method that eventually ties it to the battery. You've just used less wire to do it.

And in many cases it's easer.

 

[ShredAZ]

I personally prefer to keep any unattended battery chargers as detached from everything else in a vehicle as possible.

I'd hard wire it to the battery with a fused ISO connector and run a pigtail someplace convenient. Under a tire well or just under the hood.

I don't like vehicle fires. I especially don't like vehicle fires that burn down garages, shops and houses.

-Mac

I understand your train of thought, but the 12V power port is a direct connection to the battery. No difference in risk if I were to hardwire the charger directly to the battery.

I downsized to a 2A NOCO smart charger to give me some more headspace on the 20a circuit (not that it needed it). It's been plugged in for the last week and works great.

Thanks for the knowledge share everyone!

 

[B1Toad]

So how do you power the charger, by dragging the extension cord into the cab?

 

[macleanflood]

I understand your train of thought, but the 12V power port is a direct connection to the battery.

Absolutely! Zero argument!

My concern is the parallel conductors. All the wires that run next to that wire. The fuse box. The PDC. Possibly the PCM.

I've gone through a lot of battery tenders. I've got mowers, tractors, vehicles, motorcycles... they're all mostly cheap crap.

When one of those fuckers decides to go...I'd prefer it melt a cable that runs from the charger straight to the battery (routed to avoid collateral damage) than taking out half my dash or lighting the Jeep (and my shop) on fire.

All complete long shots. Am I paranoid? Absolutely. Have a hauled dozens and dozens of burned vehicles out of the woods...yes.

-Mac

 

[ShredAZ]

Absolutely! Zero argument!

My concern is the parallel conductors. All the wires that run next to that wire. The fuse box. The PDC. Possibly the PCM.

I've gone through a lot of battery tenders. I've got mowers, tractors, vehicles, motorcycles... they're all mostly cheap crap.

When one of those fuckers decides to go...I'd prefer it melt a cable that runs from the charger straight to the battery (routed to avoid collateral damage) than taking out half my dash or lighting the Jeep (and my shop) on fire.

All complete long shots. Am I paranoid? Absolutely. Have a hauled dozens and dozens of burned vehicles out of the woods...yes.

-Mac

100% man! I read your advice in the spirit in which it was delivered. Part of the reason I downsized to a 2A. It was always there in the back of my mind. Appreciate the advice!

 

[ShredAZ]

So how do you power the charger, by dragging the extension cord into the cab?

Terrible picture, but you get the idea. No extension cord needed. I have it mounted with 3M adhesive tape to the bottom of my garage door opener. Plenty of length in the factory cord to reach the Jeep.

 

[B1Toad]

At least you'll never have to worry about driving away with it plugged in. BTDT