It's not so long ago that trailers were little more than metal boxes equipped with axles. But things have certainly changed. Today's trailers are packed with complicated electronics that control brake lights, lane-change signals, antilock braking systems, etc.

That's why the ability to check these systems quickly and easily — without having to hunt through hundreds of wires by hand — has become so important to fleets.

Lite-Check International, Spokane, Wash., believes it has several solutions to that problem. The company makes diagnostic and testing devices for trailer lighting and braking systems.

“Trailers and trucks today are really computers with steel on top and wheels underneath,” said Robert Blair, Lite-Check's chief technology officer. “Having a way to quickly and efficiently test and diagnose all the electronic components is critical not only to maintaining safety, but also to improving productivity and keeping operational costs down.”

The company's products include an electrical tester that measures trailer circuit voltage and amperage (model 700C); a brake and light tester for trucks and trailers (model 910B); and a certification tester for trailer manufacturers and law enforcement agencies (model 911C).

Plugged into the 7-pin trailer connection slot, the devices automatically test brake lights, turning signals and brake system operation. A loud warning signal sounds if a fault is detected. The device can also test the trailer cable and tractor to make sure the fault does not lie in either of those locations.

In addition, a remote control option lets the mechanic run the test while actually walking around the trailer.

Lite-Check's testing devices, which cost between $3,000 and $5,000, weigh an average of 20 lb. and take about 30 minutes to set up.

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