Battery voltage while towing a small travel trailer

[RonAZ]

Does anyone one know if the battery voltage stays around 14 volts while towing a trailer. Mine drops to 12.7 when under power without a trailer and jumps up to around 14 when slowing dowm. "An ecectric retarder, who would have thought"
At 12.7 with line loss and the need of 1 more volt to overcome battery resistance, their is no way to recharge your RV battery while driving.
Work around is a 12v to 12v charger, but they are a bit expensive.

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[Sheepjeep]

is this a 7 ping or pin plug?

have you confirmed that there is no parasitic current draws on the trailer?

my understanding is the charging system on the JL is "smart" by changing the voltage output to be optimized for the current load so it will fluctuate and not stay the typical 14v

 

[RonAZ]

I haven't been able to plug in and test drive yet. 7 pin with tow package. I know that some vehicles like my F150 change a lot of the setting when a trailer is plugged in. I am hopeing that the JL is smart enough to keep the alternator voltage higher while towing. This is a good idea for saftey because the RV battery is also the battery that powers the breakaway brakes on the trailer.

 

[Sheepjeep]

ok yeah i think its just charging system changing to keep the optimal charge, i can image fca or any manufacturer putting a 7 pin on a car from the factory without thinking of break away charging seeing as one of the pins is a dedicated 12v line

 

[RonAZ]

Update. I installed a Redarc 12v to 12v smart battery charger in my small travel trailer. This charges the battery in the trailer up to 14.6 v not the 12.7 to 14.2 that the JL puts out. After battery is charged it floats the trailer battery at a lower voltage. If the jeep battery is too low it won't charge the trailer battery until the Jeep battery's voltage has come up. Jeep gets priority, then both get charged. Disconnects from Jeep if Jeep falls below 12.7.
Sounds great and works in the shop. Will have to wait for a camping trip to see how it works in the real world.
The factory 12v constant is not meant for much more than keeping the breakaway battery charged and a couple lights. The wire size and voltage are not meant for charging deep cycle batteries.

 

[WranglerMan]

Don’t have a trailer but my voltage pretty much stays at 14-14.2 all the time, it used to go up and down from 12.7 13.9 but now does not move the dealer advised there is nothing wrong with the charging system or batteries....go figure

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