Refrigerator / Using the rear cigarette lighter socket.

WizzBang

New member
On my 2019 JL- Can anyone tell me if the Cig Socket runs off the main or aux battery when the Jeep is off? I suspect it runs off the aux battery but want to know for sure. We are getting ready for a camping / off-roading trip to Ouray CO so I'm testing out the new camping fridge. With the Jeep off, the fridge went into low voltage cutoff almost immediately (was around 10.5v). I checked the the main battery and it read 12.4v at the terminals. I have the HD Electrical package with the 700Amp battery. Please share your experiences if you have used a fridge plugged into this socket.
 

JTCO

Meme King
On my 2019 JL- Can anyone tell me if the Cig Socket runs off the main or aux battery when the Jeep is off? I suspect it runs off the aux battery but want to know for sure. We are getting ready for a camping / off-roading trip to Ouray CO so I'm testing out the new camping fridge. With the Jeep off, the fridge went into low voltage cutoff almost immediately (was around 10.5v). I checked the the main battery and it read 12.4v at the terminals. I have the HD Electrical package with the 700Amp battery. Please share your experiences if you have used a fridge plugged into this socket.
I do not know what battery the socket runs off of, but I can't imagine that the factory wiring is heavy enough to run a fridge without overloading the circuit. The ARB kit requires 10 gauge. On another Jeep I have with a cargo outlet, I cut the wiring off of it and ran my own 10 gauge wiring to the battery instead and reinstalled the factory outlet. So it looks like an OEM outlet but the wiring is beefed up. Used it for years with my fridge with no issues.
 

WizzBang

New member
I do not know what battery the socket runs off of, but I can't imagine that the factory wiring is heavy enough to run a fridge without overloading the circuit. The ARB kit requires 10 gauge. On another Jeep I have with a cargo outlet, I cut the wiring off of it and ran my own 10 gauge wiring to the battery instead and reinstalled the factory outlet. So it looks like an OEM outlet but the wiring is beefed up. Used it for years with my fridge with no issues.
Thanks for the response. 10ga is a bit extreme for a socket limited to 15amps but depending on the fridge it might be needed. When my fridge is running , it draws about 40-45 watts which would be less than 4 amps (W / V = A). I'd suspect that the factory wiring is 12 or 14ga so it should be adequate for my use. When I charge my external power station, it draws 100w from that same socket which would be about 8.5amps. I should probably do some additional testing on this to ensure I don't blow the fuse (just to make sure it will be ok).
 

BlueRubicon

Member
Thanks for the response. 10ga is a bit extreme for a socket limited to 15amps but depending on the fridge it might be needed. When my fridge is running , it draws about 40-45 watts which would be less than 4 amps (W / V = A). I'd suspect that the factory wiring is 12 or 14ga so it should be adequate for my use. When I charge my external power station, it draws 100w from that same socket which would be about 8.5amps. I should probably do some additional testing on this to ensure I don't blow the fuse (just to make sure it will be ok).
You are confusing 15a wire size with 120v AC with 12v DC. AC current has substantially less voltage drop than DC. Running 10awg from battery in front of vehicle, to the rear would be correct thing to do for DC. The cig/12v adapter is not meant to run heavy load. Doing the math for 12v at 5 amps, x distance is how you would determine wire size You want less than 10% Vdrop. 12awg would be MINIMUM but running 10 would be better.
 

WizzBang

New member
You are confusing 15a wire size with 120v AC with 12v DC. AC current has substantially less voltage drop than DC. Running 10awg from battery in front of vehicle, to the rear would be correct thing to do for DC. The cig/12v adapter is not meant to run heavy load. Doing the math for 12v at 5 amps, x distance is how you would determine wire size You want less than 10% Vdrop. 12awg would be MINIMUM but running 10 would be better.
Perhaps the best approach would be to wire in a new socket with a larger wire size. I can leave the factory plug for other use. Anyone done this yet and if so, did you go directly to the battery or is there an open fuse I should tap into? (JL sport seems to have fuses for heated and powered seats even though they don't exist)
 

BlueRubicon

Member
Perhaps the best approach would be to wire in a new socket with a larger wire size. I can leave the factory plug for other use. Anyone done this yet and if so, did you go directly to the battery or is there an open fuse I should tap into? (JL sport seems to have fuses for heated and powered seats even though they don't exist)
I didn't do either. If you have the Rubicon (sounds like you don't?) with the AUX switches, you could pull power from one of the wires under the driver side dash above floor, or on the pass side under the hood. If you do not have the AUX switches, you could run directly off batter and install fuse block in between to protect circuit. Again...bigger the wire the better. Also make sure the wire is protected and is not going to rub anything. A wire that is energized, and gets nicked, can burn your vehicle to the ground.
 

JTCO

Meme King
Perhaps the best approach would be to wire in a new socket with a larger wire size. I can leave the factory plug for other use. Anyone done this yet and if so, did you go directly to the battery or is there an open fuse I should tap into? (JL sport seems to have fuses for heated and powered seats even though they don't exist)
What brand of fridge to you have?
 

WizzBang

New member
I didn't do either. If you have the Rubicon (sounds like you don't?) with the AUX switches, you could pull power from one of the wires under the driver side dash above floor, or on the pass side under the hood. If you do not have the AUX switches, you could run directly off batter and install fuse block in between to protect circuit. Again...bigger the wire the better. Also make sure the wire is protected and is not going to rub anything. A wire that is energized, and gets nicked, can burn your vehicle to the ground.
I do have the Aux switches, three are already in use- could wire up a new socket for the last one. Thanks for the suggestion.
 

BlueRubicon

Member
I do have the Aux switches, three are already in use- could wire up a new socket for the last one. Thanks for the suggestion.
12awg should be fine. Your unit is 45w. 45w/12v=3.75a. When your vehicle is running you will be closer to 13.5-14.2v. This will actually lower the amperage while at the higher v's. For piece of mind, when your done the wiring and have the frig plugged in and compressor is running, measure the voltage AT THE receptacle. This is most accurate way to see the vdrop. Good luck.
 

Jeeeep

Member
I run my ARB and Dometic off the rear 12v socket no issues but can't tell you which battery it runs off of.
I imagine it would be the main battery since the auxiliary battery is smaller and designated for the ESS.
10.5v cutoff is about the lowest setting as ARB and Dometic
 

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