How to Install a Hopkins Brake Controller on a 2005 Freightliner Classic Semi Truck
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Question:
how to install a hopkins brake control on a 2005 freightliner classic semi truck
asked by: Gill
Expert Reply:
When using an electric brake controller on a vehicle that vehicle needs to have the appropriate 7-Way trailer connector. Semi-trucks have a different type of 7-Way than recreational 7-Ways. If the trailer plugs into a regular 7-Way blade style trailer connector then the truck will have to have one.
If both the truck and trailer have matching 7-Ways then you would not need to change either connector. You will have to hardwire in a brake controller either way.
On any of the Hopkins brake controllers the white wire is the ground and needs to go to the negative battery terminal. The black wire is 12 volt power in to the controller and will need to connect to the positive battery terminal via a 30 amp circuit breaker # PK54530. The blue wire is output to the trailer brakes.
The red wire is input from the brake switch. Basically, it needs a dedicated brake light only signal that powers on only when you step on the brake pedal. You would use a circuit tester such as # 3808 to test the brake switch wires until you found the appropriate wire.
If the truck needs a different 7-Way then you could use installation kit # ETBC7 which will come with everything you need to install a brake controller. If you don't need a different 7-Way you can use installation kit # 5506. I have included some links that will help with this installation.

Product Page this Question was Asked From
Wiring Kit for 2, 4, 6, and 8 Brake Electric Trailer Brake Controllers
- Accessories and Parts
- Trailer Brake Controller
- Installation Kits
- etrailer
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