Setting Up A Toyota Grand Highlander For Towing A Boat Trailer With Brakes  

Question:

Expert Reply:

Welcome back, Dimitry! Been a while. ^___^

For getting your new Toyota Grand Highlander Hybrid MAX all wheel drive set up for towing, you will want to start with the Curt Trailer Hitch Receiver - Custom Fit - Class III - 2" # C26VV (if you don't already have a hitch, of course). This will actually fit a 2024 to 2026 Grand Highlander, so it's the one to get. It will also max out your capacities as it has 5,000 pounds of towing capacity and 500 pounds of tongue weight capacity. It will serve you very well.

For the wiring, you will want the Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector # C59236. Unfortunately, there are no plug and play harnesses for the Hybrid models, so this is a hardwired option. It is a bit more difficult, but just take your time and you can get it done.

From there, it's going to depend on if you still have a 5-Flat on your trailer or not. If you still do, you will need to add the Curt Trailer Connector Adapter - 4-Way Flat to 5-Way Flat - Vehicle End # C57187. This will plug into the 4-Flat, but you will need to run a wire to your reverse light (you only need to do it on one reverse light, not both). This will therein engage the electric reverse lockout on the brake actuator on your boat trailer.

If this is a different trailer with a 7-Way on it, you will need to go with the Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires # ETBC7. This will piggyback off the 4-Flat and you will need to run a few wires to the battery and inside the cab (see second image). The center port/wire on the 7-Way will also need to be run to a reverse light, just like if you were wiring up the 5-Flat.

The last thing you will need if your trailer has a 7-Way is a brake controller. For that, I highly recommend the Redarc Tow-Pro Liberty Brake Controller w/ Universal Wiring Harness - Dash Knob - Proportional # RED52VR. Redarc currently makes the best brake controllers on the market as they just work better than others. One of the really nice things about their controllers is all you will see once the install is done is the adjustment/manual override know. However, that does mean you need to drill a hole somewhere for it to go through. Most people just do that in a switch/button blank, but it is something to keep in mind.

I didn't seem to ask last time you were here, what kind of boat are you going to be towing?

expert reply by: Lazer S

0

Curt Hitch C26VV On 2026 Grand Highlander
(click to enlarge)

ETBC7 Wiring Diagram
(click to enlarge)

Dimitry F.

8/29/2026

Hi, Thanks for the response. I’ll be towing 2018 Bayliner VR5 with I/O engine and factory single-axle trailer with surge brakes. I believe total weight with trailer and equipment is around 4,400lbs. The trailer is 5 pin so I don’t think I need a 7 pin converter or a brake controller. I just need to know which kit I need to have the blue wire installed in addition to the standard 4 pin connector to disable the trailer brake on reverse.

Lazer S.

8/31/2026

@DimitryF Gotcha. You will need the following two wiring components to disable the brakes when you reverse: Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector # C59236 Curt Trailer Connector Adapter - 4-Way Flat to 5-Way Flat - Vehicle End # C57187