Connecting Ignition Switched Power From 2015 Toyota Prius v to Enclosed Trailer
Question:
Isolation is half the solution, which connectors should I use between the vehicle and trailer? Option One - use the brake wire of a 5-pole flat using: VEHICLE: Adapter 4-Pole to 5-Pole Trailer Wiring Adapter - Shorter Item # 47515 TRAILER: 5-Flat Trailer End 48" Harness Item # 20017 Curt 4-Pole Flat Vehicle Wiring Harness w/ Mounting Bracket Item # C58345 Option 2 - use the proper pin on a 7 way with VEHICLE: Adapter 4 Pole to 7 Pole Vehicle End Trailer Connector Item # 30717 TRAILER: 7-Way Molded Trailer Wire Connector, 4' Long Item # H20043 Curt 4-Pole Flat Vehicle Wiring Harness w/ Mounting Bracket Item # C58345
asked by: Sheldon T
Expert Reply:
You will need to use a circuit tester like # PTW2979 to find a wire in your 2015 Toyota Prius v that is hot only when you use your key (ignition switched power). When you do that you can simply wire in the Battery Isolation Solenoid # PK5231201, which should be wired like in the accompanying diagram with 10 gauge wire # 10-1-1.
I have added a link to a video review of the solenoid for you to check out.

Products Referenced in This Question
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
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Curt 4-Way Flat Trailer Connector w/ 60" Harness and Mounting Bracket
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Pollak Circuit Breaker - Cycling/Automatic Reset - 30 Amp - Straight Mount Bracket
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Product Page this Question was Asked From
Starter Solenoid - SPST - 12 Volt - 100 Amp - Continuous Duty - Grounded
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Sheldon T.
6/24/2019
Isolation is half the solution, which connectors should I use between the vehicle and trailer? Option One - use the brake wire of a 5-pole flat using: VEHICLE: Adapter 4-Pole to 5-Pole Trailer Wiring Adapter - Shorter Item # 47515 TRAILER: 5-Flat Trailer End 48" Harness Item # 20017 Curt 4-Pole Flat Vehicle Wiring Harness w/ Mounting Bracket Item # C58345 Option 2 - use the proper pin on a 7 way with VEHICLE: Adapter 4 Pole to 7 Pole Vehicle End Trailer Connector Item # 30717 TRAILER: 7-Way Molded Trailer Wire Connector, 4' Long Item # H20043 Curt 4-Pole Flat Vehicle Wiring Harness w/ Mounting Bracket Item # C58345