Adding a 7-Way Trailer Connector and Brake Controller to a 2003 Toyota Tacoma with 4-Way Connector
Updated 08/06/2014 | Published 08/05/2014 >
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Question:
Just purchased a 2003 Toyota Tacoma that has a good trailer hitch and a four wire plug for trailer lights on the Tacoma. I will be picking up the truck in a few days. I believe it does NOT have the optional tow package. The wiring for the existing four wire plug may have been added by UHaul or similar place. It is just a plug on the end of wires and doesnt look like a factory install. I will be towing a 2010 Forest River rpod model 171 camper that I will be picking up next month. I understand that the camper has a seven pin plug. The trailer has electric brakes. It also is set to recharge the camper battery off of the car alternator while running down the road. There also is an emergency wireinch on the camper that activates the electric brakes if the trailer disconnects while moving down the road. So I think I have a common vehicle and common trailler and need a hookup that does everything a camper connection can do. I plan to buy a brake controller and all of the plugs and wires to hook everything up from etrailer. I want the new seven pin plug actually mounted to the truck with a cover.....not just a loose plug hanging down like there is now. I plan to get some model of prodigy controller. I need info to help me decide between a P2 prodigiy controller and the prodigy RF wireless controller. Can you provide the list of materials needed and the costs for each option controller, wires, plugs, etc Also need detailed installation instructions for installing each of these? I suspect that the wiring required on the truck will be easier with the wireless unit...and need to decide whether this outweighs the added cost of the controller itself. Specific questions I have for the wireless unit...... Can the battery recharge wire and the brake controller run off the same power wire or are two separate power wires needed? Are there already wires/plugs already present on the Tacoma that I can connect to that were put there specifically for doing the trailer wiring I need to do?. Plugs and adapters specifically for Toyota will be what I want. How does the emergency disconnect brake wiring work? Assuming the four prong plug on the truck is OK, is it better to buy an adapter for the plug....or just cut it off and connect these wires to the new 7 pin plug. Any info and diagrams you can provide will be helpful. Thank You
asked by: Leo D
Expert Reply:
It does sound like a 4-Way flat was added to your 2003 Toyota Tacoma. But that is a good thing because it will be needed to install the 7-Way. To add the 7-Way (if using an in-cab brake controller) you will need installation kit # ETBC7. This provides the 7-Way, still retains the 4-Way as well, and has the wiring and accessories needed to install the brake controller. I have included some links to the right that show and explain this installation for you.
For a brake controller I recommend the P2, # 90885. It is easy to set up and use and it is reliable.
If you wanted to go with the Prodigy RF, # TK94FR, you would still need to install a 7-Way. You could either still use # ETBC7 but the installation would not be exactly the same. You would still need to wire in the 12 volt circuit and make sure that the unit is grounded to the trailer frame. The other connections described in the links for the blue and purple wires would not be required. The RF is primarily designed for one trailer that is towed by multiple vehicles.
You can few current pricing on any of these items by clicking the product links below.
Regarding the power wire a 7-Way has one 12 volt circuit on it. Multiple systems can run off this system. But it also depends on how the trailer connector is set up. If the trailer connector has a wire that goes to 12 volt powered things and then a separate connection from a different pin on the connector to the battery then you would likely need to wire the yellow wire on the new 7-Way to the battery or alternator. The 12 volt circuit on a 7-Way will provide a maintenance charger only to a trailer mounted battery. It will not charge up a battery.
Your Tacoma is already set up as much as it can be for adding a 7-Way/brake controller.
A breakaway system works by apply voltage to the trailer brakes if the trailer becomes disconnected from the tow vehicle. There is cable that you will attach to the tow vehicle. The cable goes to a plastic pin on a switch on the trailer. When the pin is pulled out 2 metal contacts inside touch completing a circuit from the trailer battery to the electric brakes on the trailer.
Since the ETBC7 requires plugging in the 4-Way you will want to leave it as is.
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