SeaSense 50080310 4-Way Circuit Tester EZ Troubleshooter II for Trailer Wiring

The SeaSense EZ Troubleshooter II is a professional-grade circuit tester designed to quickly diagnose electrical issues in 4-way flat trailer wiring systems. This essential diagnostic tool plugs directly into your vehicle's standard 4-prong flat towing connector to verify proper power delivery to trailer lights without the need for an actual trailer connection.

Key Features:

• Four independent green LED indicators show real-time power status for each circuit
• Built-in male and female connectors allow inline installation—tester remains connected while towing
• Waterproof PVC construction withstands harsh marine and outdoor environments
• Tests turn signals (left and right), tail lights, and brake lights instantly
• No tools required—simply plug in and operate vehicle lighting controls
• Eliminates guesswork when troubleshooting trailer lighting problems

This circuit tester is ideal for boat trailers, utility trailers, and small cargo trailers using standard 4-way flat wiring systems. The pass-through design means you can verify circuits before each trip without disconnecting the tester, saving valuable time during pre-tow safety checks. Essential for anyone who regularly tows trailers and needs to quickly identify wiring faults at the vehicle connector.