Getting a Brake Signal to Install a Brake Controller on a 2003 Toyota Tundra

Question:

I had toyota hookup a 7 way and add a reciever type hitch when I bought the truck. I just got a travel trailer that has electric brakes ans want to install a brake controller. Toyota shop only ran 4 wires to the seven way plug, so now I need to run the charge, brake controller etc. My main problem is there is literally no room to tap into the cold side of the brake switch. Can I run a wire all the way from the truck brake light where there is room to work? Thanks for your help, if that is not possible can you tell me how to release the wire from the brake switch where I could maybe pull it down far enough to tap into? I will need to purchase a controller and some breakers

asked by: Wade

Expert Reply:

You do not want to tap into the brake light on the truck to get the brake signal for the brake controller. There is a closer and easier approach if the brake switch is not accessible. Use the vehicle owners manual to find the location of the stop light fuse or CHMSL fuse. Then you can use a fuse tap, like # F2526, to tap into that circuit and get the require brake light only signal. Make sure that the fuse tap you use is the appropriate size for the stop light or CHMSL fuse in your truck.

On the 7-Way that was installed on your truck, for the 12 volt power circuit, you will need a 40 amp circuit beaker, # PK54540, I recommend some duplex wire # 10-2-1 sold in 1 foot increments. This will be easier to route than 2 separate wires since the brake output wire to the blue wire on the brake controller also needs to be connected.

You can follow the parts of the FAQ and video that apply to your installation that I have linked for you.

expert reply by: Michael H