(306) 485-8486





since 1994

 Light Tester Instructions

HMT112 testers include everything you need to test lighting circuits on tractors/trailers, RVs and farm equipment.

The vehicle testers are easy to understand and use which will quickly help solve major problems that can occur frequently. Problems such as reversed wiring, cross shorts, open grounds, lack of ABS brake signals. Experience has shown that using a Hall Electronics trailer tester for troubleshooting can save as much as 50 percent of the time required finding and correcting lighting circuit problems. 

 All testers include an amp meter to monitor current draw for each test.

 All Testers include a master power switch to disconnect power.

The HMT112 Deluxe has a battery & charger mounted on the base. (battery purchased separately)

All testers include easy to understand test instructions.

The testers all detect and display ABS brake signals from the tractor.

All testers are fully warranted for one year from defects in parts and workmanship. 12) All circuit components in testers can be bought locally and changed within minutes.


The "BOX" will perform many electrical tests on all types of trucks and trailers, R.V.'s and farm equipment. -Will determine if a problem exists -Locate where the problem is - truck or trailer -Determine if it is an open or short circuit -Test draw in amps in each circuit -You can leave circuit breaker trip until you find short in wire


You have the option to hook "The Box" up to a 12 volt battery charger or to a 12 volt battery. RED TO POSITIVE - BLACK TO NEGATIVE Check Tractor (Truck) -Plug trailer cord in the "Box" -Turn all switches on the "Box" to Off -Operate the following functions in cab *Aux. Power *Park Lights *Left Signal *Brake or Stop Lights *Right Signal *Marker Lights Watch Indicator Lights on "Box" -Indicator lights should correspond with tractor -No light indicates bad switch, or circuit breaker, or light cord -Wrong light comes on indicates incorrect wiring Switch all tractor controls to Off and operate "Box" controls to power up tractor lights. *Park lights may have a relay in line and may not power up. TRAILER CHECK -Turn all "Box" switches to Off -Turn on main power -Operate individual switches to locate problem Watch For The Following Conditions: Open Circuit- Light on and no draw indicates broken wire or burnt out light bulb Short Circuit- More than one light is on or circuit breaker is tripping or higher than normal amperage for that circuit, this indicates that wires are in contact with one another or in contact with ground Open Ground Circuit- All indicator lights are on and there is no amperage (ground wire is broken or disconnected).