Where to Splice Brake Light Wire From Brake Controller To Stoplight Wire
Question:
on the brake pedal wiring which wire should the red wire for my controller be connected. My truck did not come with the pre wired plug?
asked by: BG
Expert Reply:
Since your vehicle does not have a brake controller port, you will want to use a universal wiring pigtail. For example, if you have a Tekonsha brake controller, you could use a Plug-In Harness for Tekonsha and Draw-Tite Brake Controllers # 20127. You will want to use a circuit tester, like # PTW2993, to test the wires at the stoplight switch at the back of your brake pedal to find the wire that only has signal when the brake pedal is depressed.
Once you have found the wire that only produces signal when the brake pedal is depressed, you will want to splice in your red wire from your brake controller harness. You can use a splice like the quick splice # SWC502905-1.
The red wire can be spliced with the stoplight wire at any spot in the wire, just be sure you will have enough wire to reach your brake controller.
I have attached a diagram on splicing in a brake controller for you, as well as a help article on installing a brake controller.
Products Referenced in This Question
Quick Splices - Self-Stripping Connector - Closed Port - 14-16-18 Gauge - Blue - Qty 1
- Wiring
- Wire Connectors
- Quick Splice Connectors
- 18-16-14 Gauge
- Spectro
more information >
Product Page this Question was Asked From
Replacement Brake Control Plug-In Harness for Tekonsha and Draw-Tite Brake Controller 12" Long
- Accessories and Parts
- Trailer Brake Controller
- Wiring Adapter
- Plugs into Brake Controller
- Universal
- Draw-Tite
more information >
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Excellent 2.
5/26/2024
With the latest cars, it's a very good idea to place a diode in the RED wire to prevent voltage from the controller feeding back into the stoplight switch wiring harness. Feedback from the controller can cause all kinds of problems with cruise control, error codes, shifter locking up etc. I'm using the universal harness you suggest # 20127, but will place one diode (as noted above) in the RED wire and another diode in the BLUE wire to prevent trailer battery feedback from going back into the controller. Hope this helps someone avoid having problems after a brake controller install.