What Is The Purpose Of Fifth Wire On Vehicle-Side Brake Controller Port On 2008 Toyota Tundra
Question:
interested in 3040-P Tekonsha Brake controller wiring adapter for 2008 Tundra. 4.7Ltr, double cab, SR5 Off Road equipped. The connector in the truck has a white connector female with 5 wires. The wiring harness 3040-P has only 4 wires with the white one outside of harness for physical ground connection. what is the reason for 5 wires on the truck side? what is the reason the white wire is not part of the harness through the truck? Will the 3040-P harness work on my Tundra?
asked by: Marc
Helpful Expert Reply:
The fifth wire on the Tundra brake controller connector is for illumination. This is not used on any of the brake controller we carry and when you install the Tekonsha # 3040-P plug-in adapter, the fifth wire is basically ignored.
The 3040-P is confirmed as a fit for your Tundra, but it is designed for Draw-Tite # 5504 and Tekonsha, # 39523, # 90885, # 90195, # TK90160, and # 39510 brake controllers.
If you do not have a brake controller for your Tundra, I recommend the Prodigy P2, part # 90885. This is one of our most popular brake controllers because it is easy to install and operate.

Products Referenced in This Question
Tekonsha Voyager Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Splice-In
- Under-Dash Box
- Under-Dash
- Up to 4 Axles
- Indicator Lights
- Single Trailer Only
- Tekonsha
more information >
Tekonsha POD Trailer Brake Controller - 1 to 2 Axles - Time Delayed
- Trailer Brake Controller
- Time Delayed Controller
- Electric
- Plug-In
- Under-Dash Box
- Under-Dash
- Up to 2 Axles
- Indicator Lights
- Single Trailer Only
- Tekonsha
more information >
Draw-Tite Activator IV Trailer Brake Controller - Up to 4 Axles - Time Delayed
- Trailer Brake Controller
- Time Delayed Controller
- Electric
- Plug-In
- Under-Dash Box
- Under-Dash
- Up to 4 Axles
- LED Display
- Single Trailer Only
- Draw-Tite
more information >
Tekonsha Prodigy P3 Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Electric over Hydraulic
- Splice-In
- Under-Dash Box
- Under-Dash
- Up to 4 Axles
- LCD Display
- Multiple Trailers
- Tekonsha
more information >
Tekonsha Prodigy P2 Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Electric over Hydraulic
- Splice-In
- Under-Dash Box
- Under-Dash
- Up to 4 Axles
- LED Display
- Single Trailer Only
- Tekonsha
more information >
Tekonsha Primus IQ Trailer Brake Controller - Up to 3 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Splice-In
- Under-Dash Box
- Under-Dash
- Up to 3 Axles
- LED Display
- Single Trailer Only
- Tekonsha
more information >
Product Page this Question was Asked From
Tekonsha Plug-In Wiring Adapter for Electric Brake Controllers - Toyota and Lexus
- Accessories and Parts
- Trailer Brake Controller
- Wiring Adapter
- Plugs into Brake Controller
- Vehicle Specific
- Tekonsha
more information >
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