I am installing a brake controller on my trailer. Among other things this thing allows me to connect my camper with trailer brakes to a Flat-4 Hookup. The link is below. My question is the way the thing gets power with the flat-4 is the running lights power. If I simply Jumper the 12VDC line from the Running lights line in my 7-way (Camper) to 4-flat adapter (Car) adapter will it work Okay and also charge the coach batteries. Or will it blow up? (Melt wires/blow fuses)I'm looking for anyone that has tried to charge coach batteries, or simply powered a refrigerator, from a flat-4 running lights lead, (running lights must be turned on).Thank you for any help.AUTOWBRAKE

No, the flat 4 cannot carry that kind of load.

I replaced the flat-4 with a 7-pin.Any decent trailer, RV or hitch shop can do the swap.etrailer probably has what you need:https://www.etrailer.com/dept-pg-Wiring-sf-Trailer_Connectors.aspx

ScottG wrote:No, the flat 4 cannot carry that kind of load.Wires are wayyyyy undersized to help you.

Very clever idea1. IF your Trailer battery is bad or dead or below 11 volts, you will NOT have Trailer Brakes at all2. 4 Way flat gauge wiring cannot supply the needed power, especially if you attempt to tie into the Running light circuit. AND, I would worry about the Tow vehicles gauge wiring and fuse set up in its running circuit.3. This system needs to be installed with a standard 7 way Bargman Trailer plug, that has the required Charge line run to the trailer. If no charge line to the trailer from the tow vehicle, the Brake system will slowly deplete the Trailer battery every time the brake system engages. 4. IF you have a 4 way flat on your truck(tow vehicle) AND your trailer, something is wrong unless the trailer is a utility trailer. RV camping trailers always have a 7 way Bargman plug on the trailer.

Watch the review by e-trailer. They don't recommend using on the 4 wire because the wiring is not heavy enough.

Charging Camper/Coach Battery with Running Lights Lead from Flat-4

bikendan
Explorer
Feb 10, 2020
Sounds like someone should've bought a vehicle with a real factory tow package.
Lwiddis
Explorer II
Feb 10, 2020
Solar is a very natural recharging method, Naturist.
Roger10378
Explorer II
Feb 10, 2020
Watch the review by e-trailer. They don't recommend using on the 4 wire because the wiring is not heavy enough.
dougrainer
Nomad
Feb 10, 2020
Very clever idea
1. IF your Trailer battery is bad or dead or below 11 volts, you will NOT have Trailer Brakes at all
2. 4 Way flat gauge wiring cannot supply the needed power, especially if you attempt to tie into the Running light circuit. AND, I would worry about the Tow vehicles gauge wiring and fuse set up in its running circuit.
3. This system needs to be installed with a standard 7 way Bargman Trailer plug, that has the required Charge line run to the trailer. If no charge line to the trailer from the tow vehicle, the Brake system will slowly deplete the Trailer battery every time the brake system engages.
4. IF you have a 4 way flat on your truck(tow vehicle) AND your trailer, something is wrong unless the trailer is a utility trailer. RV camping trailers always have a 7 way Bargman plug on the trailer.
jdc1
Explorer II
Feb 10, 2020
ScottG wrote:
No, the flat 4 cannot carry that kind of load.

Wires are wayyyyy undersized to help you.
time2roll
Nomad
Feb 10, 2020
I replaced the flat-4 with a 7-pin.
Any decent trailer, RV or hitch shop can do the swap.

etrailer probably has what you need:
https://www.etrailer.com/dept-pg-Wiring-sf-Trailer_Connectors.aspx
ScottG
Nomad
Feb 10, 2020
No, the flat 4 cannot carry that kind of load.

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