How Do I Wire a 2005 Toyota Tacoma for a Brake Controller and 7-Way

Expert Reply:

This adapter will not provide the additional wiring needed for adding a brake controller. This product steps a 7-Way down to a 4/5-Way, not the reverse.

What you need instead is a 7-Way Wiring kit like part # ETBC7. If the trailer connector you have on your Tacoma is the factory installed connector, it is actually a 4-Way connector.

You will plug the 4-Way on the van into the ETBC7 harness, and like that, half of the functions are wired.

There are 4 loose wires on the 7-Way that you will need to connect to finish the install. The white wire with the eye ring terminal is the ground. Connect this to the vehicle frame. The purple wire is for reverse lights. If your trailer does not have reverse lights, you can tape this wire out of the way on the vehicle in case you need to reverse lights later.

Next you have just the blue and black wires remaining. Connect these two to the included length of jacketed 2-wire, and run them up to the engine bay. The black wire needs to go to the positive post of the battery, with a 40-amp breaker wired in-line. The blue needs to go through the fire wall into the foot box for the brake controller.

Most brake controllers have 4 wires, a red, blue, black and white. Most use the following wire code, but check with the owner manual of whatever brake controller you use. The black wire needs to go into the engine bay to the positive post of the battery. Again use the 20 or 30-amp circuit breaker, check the owner manual of the controller to see which is needed. The white wire goes to the negative post on the battery. The blue wire connects to the blue wire you ran up from ETBC7. The red wire needs to be connected to a stoplight circuit. Follow your brake pedal up till you find a switch. One of the wires will show 12V only when pedal is pressed. You may need to use a circuit tester or a multi-meter to identify this wire. Splice the red wire into this wire.

At this point the brake controller and 7-Way wiring on the vehicle is all complete. A properly wired trailer with a 7-Way will plug right in and work.

For a brake controller, I would recommend the Tekonsha Prodigy P2, part # 90885. It is a very effective, very easy to use brake controller. It just replaced its predecessor and has brought some nice new features to the table. I have added a link to a question I answered about the differences between the P2 and its predecessor.

expert reply by: Patrick B