Built for 7-Way Round Tractor Trailers – Rugged, Water-Resistant, and Made in the USA

The Heavy Ranger® MUTT® is a rugged, water-resistant trailer tester designed for commercial trailers with 7-way round (SAE J560) pin connections. It utilizes a DeWalt® compatible 20V battery to power each trailer circuit—no truck required—to verify wiring configuration, ground integrity, short circuits, brake light function and turn signal operation..

Built for reliability in shop or yard environments, this standalone unit speeds up diagnostics, prevents blown fuses and
eliminates guesswork. With built-in short circuit protection, rugged construction, and USA-made quality, it’s a must-have for technicians and trailer owners.

Features and Benefits

• Tests 7-way round (SAE J560) pin tractor trailer harnesses without connecting to a truck
• Simulates turn signals, brake lights and 12V power for system verification
• Power up ABS circuit for blink diagnostics
• Visual LED confirms power output at each circuit
• Rugged, water-resistant design for field or shop use
• Internal DeWalt® 20V compatible battery adapter
  (battery not included