I have a load rite flat 5 pin connector from my boat trailer and the Tacoma has a seven pin connector. I purchased a 7 pin to 4 and five pin flat adapter. The trailer has surge brakes I would like to hook up. Toyota provided me with a connector for the brakes but Im not sure how to splice into the reverse light wire on my vehicle.
asked by: Tom
It sounds like you have a factory 7-Way connector on your 2012 Toyota Tacoma and that you also have the dealer supplied electric brake controller wiring harness for wiring an electric brake controller in the cab of your vehicle.
Since your boat trailer is equipped with surge brakes, you will not need to install an electric brake controller in the cab of your Tacoma.
The first thing you should do is check the center pole, see photo, in the 7-Way connector on your vehicle with a circuit tester like part # 3808. The center pole should show power when the vehicle is shifted into reverse. Be sure to have the emergency brake applied and someone in the vehicle holding the brake, for safety. The key must be in the on position but the engine need not be running.
If you have power at the center pole in the 7-Way connector when the vehicle is in reverse, then you do not need to do any additional wiring on the Tacoma.
Next, if the vehicle 7-Way is working, check the adapter you purchased, part # A75TB. The adapter should show power on the outer post opposite the ground post when installed in the vehicle 7-Way and the vehicle is in reverse, see attached photo. If not the adapter is not working correctly and would need to be replaced.
If the adapter is working correctly you will need to be sure that the 5-Way connector on your trailer is wired correctly to the electric lockout solenoid, like part # T4748800, that is inline with the master cylinder and trailer brake lines. Make sure the correct wire from the trailer connector is routed to the power wire for the solenoid and that the solenoid is correctly grounded to the trailer frame and that the ground wire from the trailer connector is grounded properly also.
If you find that the vehicle 7-Way is not working you will need to access the wires coming from the back of the factory 7-Way and determine which wire powers the center pole inside the 7-Way. This can be done with a multimeter tester like part # BTMT15. Once you find the correct wire, sever it and attach a length of 12 gauge wire, part # 12-1-1, to this wire and run it to the reverse light wire at the back of the vehicle taillights.
expert reply by: Bob G
Products Referenced in This Question
Tools for Wiring
Tools for Wiring
Brake Actuator Parts
Master Cylinder Parts
Product Page this Question was Asked From
Single Function Adapter
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