FaultFinder: Open and short circuit finder and tracer

Discontinued - see FF310 for new improved model

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  The FF300 is easy and flexible to use. It only requires connecting the transmitter in series with the circuit or wire under test, (i.e.: in place of a blown fuse, across a connector, in series with an open wire, a light bulb socket, etc.), and scanning the circuit/wire with the tracer's flexible probe to find the trouble spot.

  This professional tool will work on all kinds of circuits with voltages between 6 and 36 Volt DC, such as those found in automobiles, trucks, trailers, tractors, boats, RVs, etc… With its wide working voltage range, automatic open/short detection, flexible probe and adjustable sensitivity, the FF300 Faultfinder enables you, to troubleshoot a complete array of common problems, in a wide variety of vehicles.

  Now with the FF300 you can locate short circuits, broken wires, current leaks and perform wire tracing quickly and easily spending only a fraction of the time and effort required when using conventional methods. In most cases, you will even be able to locate the problem area without having to untie harnesses, open conduits or remove panels.


General Technologies Corp. FF300 Fault Finder open and short circuit tracer

Technical Specifications

FF300T (Transmitter)

FF300R (Receiver)

Electrical Specifications

  • Input Voltage range: 6 to 36 Volt DC
  • Input DC Current: Unlimited (internally limited)
  • Voltage output: 5 Volt DC maximum
  • Current Output: 200 mA DCrms maximum


  • Short circuit tracing
  • Open circuit tracing
  • Wire identification
  • Wire/Circuit tracing
  • Ground connections checks

For use in

  • Automobiles
  • Trucks
  • Trailers
  • Boats
  • RVs
  • Any 6 to 36 Volt DC powered circuits


  • FF300T ( transmitter)
  • FF300R (receiver)
  • Hard padded case for carrying and storage
  • User's Manual