7 pin connection with shore power - 2016 T@G

dsarthur

So I have a few questions regarding keeping the trailer power attached to car.
How long can I keep it attached with the car off? Will it drain the car battery if I go into a restaurant for an hour? I am always worried about this.
Can I leave it attached to the car power when I am hooked up to shore power at a campsite?

Chaverim

It will continue to draw power from the car’s 12v battery, even at a slow rate. That said, what I do is usually leave the car attached to the car hitch, and just unplug the 7 pin.

LuckyJ

It will equalize the draw from both batteries.

If you TD battery last a full day, then adding the battery should give it extra time and that will depend of you TV batterie. Honda's usualy have smaller batteries, in my wrangler, I have updated to a deep cycle 800 amp batterie, tye biggest I could fit in the hole and over.

So no worries for my for an overnight plug in. But all depends on how you use power. But for a lunch stop, I would not worry about it.

Just one thing, I would suggest that you place something on your steering wheel to remind you to plug the trailer cord. Cause no electical, no brake and flasher or driving light, and this could be very very dangerous while on the road.

Sharon_is_SAM

If you have an isolation relay on your TV, then the current will stop when the ignition is off.
If no isolation relay, and you have a fully charged TaB battery, your only serious draw would be the Norcold chest style frig. That is pretty efficient (about 4 amps when it cycles, 1 amp in between). I think you would be fine for a lunch break, or turn off the frig and keep the lid closed - just remember to turn it back on.

Have you measured your voltage with the frig on and the 7 pin disconnected?

Regarding maintaining a 7 pin connection while the TaG is connected to ac - If there was a power surge or a large short circuit, not sure if your TV and/or battery would be at risk (not to mention your TaG). If you are on shore power, I see no reason to keep your 7 pin connected. I checked “etrailer” and they reported that it may result in trickle charging your TV battery

dsarthur

Thanks everyone

Ianstag

We left ours connected yesterday while we ate. It was parked in the sun. No problems.

Ianstag

Can you please explain the "isolation relay" for the TV? Does TV mean tow vehicle? If so where where can I get an isolation relay?

Sharon_is_SAM

TV in this context is tow vehicle. See link for a better explanation than I could ever give you😁. I would check with your auto dealer service manager first and if they won’t install it, then a reputable after-market installer can do the job.

http://www.dieselhub.com/towing/split-charge-trailer-battery-isolator.html

Ianstag

Thanks.

Sharon_is_SAM

I sent a message to Mike Sokol - RVTravel.net electric guru regarding being hooked up to shore power and attached to the TV via 7 pin at the same time. He reported that since the AC power is separated from the DC power, it would be ok to leave it connected only if you have an isolation relay. Without it you risk the draw down of the TV battery or the possibility of the TaB converter actually charging the TV battery.

"Charging circuits are very sensitive to battery chemistry and size, so intermixing your RV and Vehicle batteries, especially during charging, is a bad idea."

So, if you have an isolation relay, you can safely leave the RV hooked to shore power and to the TV via a 7 pin. If no isolation relay, disconnect from the TV while plugged into shore power.

prrofessor

I drive a 2018 Honda Ridgeline. The power to the 7 pin trailer plug has power only when the engine is running.