Wiring for 2008 Toyota Tundra Towing Surge-Coupler Equipped Boat Trailer With 5 Pole Connector

Question:

I have a four prong connecter on my 08 Tundra. I bought a boat and the trailer has a five prong connector. The trailer does not have electric brakes, it has a surge brake. Will this work??

asked by: Don W

Expert Reply:

A brake controller like the Tekonsha # 90885 P2 is for use with electric brakes, not surge brakes like what your trailer is equipped with, so you wouldn't need a brake controller.

A surge coupler will compress when the tow vehicle applies its brakes. This compression is what applies the hydraulic trailer brakes and is in effect, just like stepping on a brake pedal. The 5th wire on your trailer connector is for a reverse lockout solenoid which prevents the brakes from actuating when you back the trailer.

There are two primary solutions to installing a compatible trailer connector on your Tundra. You can use an adapter like # 20036 which would work well if you tow other trailers. The blue wire on the truck side would tap into the truck's reverse lamp circuit using the included quick splice connector.

Another option would be to cut off the existing 4 pole connector on your vehicle and replace it with a 5 pole connector, part # HM37908. You could use heat shrink butt connectors like # DW05744-5 to connect the right turn/brake lamp, left turn/brake lamp, running lamp and ground connection and a quick splice connector like # SWC502905-1 to connect the blue wire on the 5 pole connector to the reverse lamp circuit.
With this option, you wouldn't need to fool with an adapter.

I've linked to some product videos that you might find helpful.