How to Install Auxiliary 12 Volt Battery Charge Circuit on a 2007 Toyota Highlander Hybrid
Question:
I have a 4 pin to 7 pin plug from HH to camper. But there is no battery charge. Is the HH auxillary battery strong enough to charge camper battery and how? Can I just run a hot wire from the auxillary battery to the 7 pin plug?
asked by: Judy
Expert Reply:
Yes, you can use the 12 volt battery in your 2008 Toyota Highlander Hybrid to help maintain the charge on your camper battery when the vehicle is running. Vehicle charging systems do not provide enough output to charge a trailer mounted battery from a discharged state, even if they are not Hybrid vehicles, so you will need to bring your trailer battery up to full charge with a battery charger before leaving on a trip.
You could wire a charge circuit to the adapter you chose, # C57674. You would need an appropriate length of 10 gauge wire, # 10-1-1, to go from the 12 volt battery positive post to the black wire at the back of the connector, and you would need to install a 40 amp circuit breaker, # PK54540, inline on that wire, to protect the circuit from short circuit situations.
If you need a brake controller also, most likely you do if you are towing a camper with a 7-Way connector with your Highlander, a better option would be to use our brake controller installation kit, # ETBC7, since your Highlander Hybrid has the 4-way connector already installed.
The ETBC7 kit includes everything you will need to install the brake controller, 12 volt power line, and trailer connector in one package and can be done with a professional look if you take your time. I do not have a video yet on the Highlander Hybrid but I have linked a video with the installation of the ETBC7. You will not need the 4-way T-One wiring with a factory 4-way already installed. We also have detailed installation instructions, see link.
For a brake controller, I would recommend the P-3 brake controller, # 90195, for your Highlander Hybrid, because it is easy to use and set up and gets great reviews from our customers who have used it.
Products Referenced in This Question
Tekonsha Prodigy P3 Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Electric over Hydraulic
- Automatic Leveling
- Under-Dash Box
- Dash Mount
- Up to 4 Axles
- LCD Display
- Up to 360 Degrees
- Tekonsha
more information >
Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires
- Accessories and Parts
- Trailer Brake Controller
- Installation Kits
- etrailer
more information >
Pollak Circuit Breaker - Cycling/Automatic Reset - 40 Amp - Straight Mount Bracket
- Accessories and Parts
- Wiring
- Circuit Breaker
- 40 Amp
- Pollak
more information >
Product Page this Question was Asked From
Adapter 4 Pole to 7 Pole and 4 Pole w/Test Lamps
- Trailer Wiring
- Wiring Adapters
- Multi-Function Adapter
- 4 Flat
- Plug and Lead
- 4 Flat
- 7 Round - Blade
- CURT
more information >
Featured Help Information
Instructions
Miscellaneous Media
Continue Researching
- Shop: Trailer Wiring
- Search Results: propane gauge
- Video: etrailer Trailer Brake Controller Universal Kit Installation - 2019 Toyota Highlander
- Shop: Camco Propane Cylinder Gas Gauge and Leak Detector
- Shop: Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires
- Shop: Replacement Standard Cradles for Hollywood Racks Hanging Bike Racks - 1" Arms - Qty 2
- Shop: RV Power Cord
- Shop: RV Electrical
- Shop: Epicord Hardwire RV Power Cord w/ Pull Handle - 30 Amp - 30'
- Shop: Brake Controller
- Shop: Hopkins Plug-In Simple Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Shop: Camco RV Polyethylene Propane Tank Cover for (1) 20-lb Steel Tank - Polar White
- Shop: Mighty Cord RV Extension Cord w/ Pull Handle - 30 Amp - 50'
- Search Results: toyota highlander wiring harness
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Video: Hopkins Custom Fit Vehicle Wiring - Trailer Hitch Wiring - HM11141845 Review
- Video: Hopkins Plug-In Simple Vehicle Wiring Harness Installation - 2018 Toyota Highlander
- Shop: RV Covers
- Video: etrailer Universal Kit for a Trailer Brake Controller Installation - 2015 Toyota Highlander
- Video: Hollywood Racks Bike Carrier Standard Cradles Replacement Review
- Video: Hollywood Racks Hitch Bike Racks HR740-P Review
- Shop: Trailer Hitch
- Video: Redarc Tow-Pro Liberty Brake Controller Installation - 2019 Toyota Highlander
- Search Results: replacement bulbs
- Q&A: Trailer Wiring 4-Way Recommendation for 2017 Toyota Highlander
- Q&A: Replacement Light Bulbs To Convert To LED Light
- Shop: RV Interior Lighting
- Search Results: trailer brake controller
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Search Results: etbc7