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Square Wheel Industries Introduces Brake and Light Diagnostic Unit for Mobile Service Trucks

Square Wheel Industries has introduced a faster, more efficient method of testing the trailer light and air brake system that can easily be fit to mobile service trucks

by Staff
April 22, 2009
2 min to read


Square Wheel Industries has introduced a faster, more efficient method of testing the trailer light and air brake system that can easily be fit to mobile service trucks.


With the Express Mobile, all lighting functions and the air brake system (including brake adjustment) can easily be checked in just two minutes. An isolation valve on the unit allows leak down tests on individual air valves.

The Express Mobile is able to accomplish this because of the radio remote-controlled air brake operation in addition to a complete built-in electrical system scanner. The Express Mobile scanner function allows testing of lighting in sequence (left/center/right) to help isolate shorts or improper wiring. The remote control function turns 'walk around time' into productive diagnostic time.

Modern ABS computers test themselves when the trailer's auxiliary circuit is first powered or, on some systems, each time the stop light circuit is powered. The Express Mobiletm simply powers a trailer's circuits to initiate this self test.

The Express Mobile has a handy ABS test switch to control the auxiliary and stop light circuits with the remote. This allows initiation of the ABS self-test from behind the trailer.
No longer is it a necessity to be in two places at once, i.e. running up to the tractor to turn the lights on and then running to the trailer to see if they are operating correctly.

For further information on the Express Mobiletm visit the Square Wheel Industries website, www.squarewheelindustries.com.

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