Parts Needed to Install a P2 Trailer Brake Controller on a 2005 Toyota Tacoma

Question:

I have 2005 toyota tacoma with factory 4 plug what else do Ihave to hook up, I already mounted my 7 plug and wired in the factory plug. what else and were do they go.

asked by: Jerry H

Expert Reply:

If your 2005 Toyota Tacoma came with a factory tow package then to install your P2 brake controller # 90885, you would need wiring harness # 3040-P. It plugs into the factory port on the truck. I have included a link to the installation instructions for you.

If you have the factory wiring harness with black/red, green/white, brown, red, and flat green wires then you can hardwire in the controller as follows:

Black/red goes to brake controller black for 12 volt power
Green/white goes to brake controller red for input from the brake switch
Brown goes to brake controller white for ground
Red goes to brake controller blue for output to the trailer brakes
Green is not used

If your truck did not come with the factory tow package (which would have included a factory 7-Way connector) then you will need to do a little hardwiring using kit # 5506.

To install you would mount the brake controller according to the instructions. Then you would attach a length of wire to the back of the 7-Way in the 7:00 position. Route the wire under the truck, avoiding areas that could damage or melt the wire, and up into the engine compartment. Then route it through the firewall and attach it to the blue wire on the brake controller.

Next you will need to attach some of the wire to the black and white brake controller wires, route them through the firewall and into the engine compartment. The white wire will ground to the negative battery terminal. The black wire will go to the included circuit breaker in the kit on the AUX post. The circuit breaker gets mounted to the metal of the engine compartment for ground. Then run a length of wire from the BAT post to the positive battery terminal.

For the red wire you will need a circuit tester like # PTW2993 if needed. Test the wires on the brake switch, located above the brake pedal. You need the wire that shows a signal only when the brake pedal is pressed and not when the headlights or turn signals are on.

If the 7-Way you have needs to be completed then you would connect the black wire to the positive battery terminal via a 40 amp circuit breaker # PK54540. The wire from the center post is for reverse lights and you will tap into a reverse light wire on the truck. If the trailer does not have reverse lights or if it does not need 12 volt power you do not have to connect these wires. they can be taped up and stowed out of the way. The white wire will need to ground to the truck frame.

I have included some links that will help with this installation.