Why Does Brake Controller Harness for 2018 Toyota Tacoma Have Ground Wire


I just purchased a 2018 Tacoma TRD Off Road and need to install a brake controller. Since the truck is prewired it looks like a simple plug in set up. I have two questions. First, why do I need to attach a ground wire? Second, any suggestions for mounting? Drilling in the small lip under the dash in front of the connector? Two sided tape? I may consider wireless if you give me the part #’s and pricing. Thanks for the help


Expert Reply:

That's a common question and the reason Wiring Adapter for Trailer Brake Controllers # 3031-P has a ground wire on it is because some models of Tacoma and Tundra, such as your 2018 Toyota Tacoma, have an insufficient ground at the factory connection and this adapter remedies that potential issue.

While there are wireless options like the Curt Echo # C51180, I very strongly recommend going with the Prodigy P3 # 90195. The P3 is easy to use, levels automatically, has constant diagnostic checks, contains safeguards which defend your controller against shorts and features an LCD display which is much easier to read than that of other controllers.

This controller has been met with nearly universal praise; it has been reviewed by our customers nearly 3,000 times and is averaging close to 5 out of 5 stars.

As for the mounting the most popular spot for the P3 # 90195 on your Tacoma seems to be just to the left of the steering wheel and close to where the harness connects. I have added a couple of photos for you to check out that our customers have sent in showing how they mounted it in their Tacomas.

Click to Enlarge
expert reply by:
Kyle S

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