Circuit Chaser ® Instructions

Find and temporarily repair short or faulty circuits in the shop or on the road.


att_circuitchaser_jumpers.pngIn the shop, use the Circuit Chaser® to test your cable, tractor and trailer. On the road, it provides a fast and safe temporary repair by allowing you to isolate a fault in the tractor or cable, by-pass it, putting power to the required circuit on the trailer. With Circuit Chaser you are back on the road in minutes.

Testing Circuits: Plug the Circuit Chaser into the end of the cable nearest the trailer. Bring the cable into the cab and run through each circuit of your lighting system. If one or more of the LED’s do not come on as its circuit is being checked that circuit is faulty. Note: The second set of LED’s work only on negative ground trucks. To determine where the fault is located, unplug the Circuit Chaser and move it to the seven pin connector on the tractor. Re-check each circuit. If all the LED’s light, the problem is in the cable. If one or more of the LED’s remains unlit during the test, the problem is in the tractor. You may also use the Circuit Chaser to test your trailer by checking at the seven pin connector on the rear of the trailer. When using the indicator markings to identify the faulty circuit, the Circuit Chaser must be plugged into the seven pin connector on the tractor for proper orientation.

att_plugin_female.pngBy-Pass Feature: To by-pass a short or faulty line until permanent repairs can be made, plug the Circuit Chaser into the cable end nearest the trailer, making sure that the pins point toward the tractor. Identify the faulty circuit. (1) Unplug the unit and unscrew the pin on the line next to the unlit LED, to isolate the fault. (2) Install the flat brass jumper strap over the center pin and bend the tail down into the hole where the pin was removed. Plug the cable and attached Circuit Chaser into the trailer and you can proceed down the road. If all the lights do not come on, follow the above procedure for the other faulty circuits. The Circuit Chaser may also be used to by-pass a fault in the first trailer, when pulling doubles. In order for the by-pass feature to work: Power must be available on the center pin. Pins must point toward the tractor. The Circuit Chaser works best with connectors that are 1.5 inches in depth.

att_plugin_male.pngTrouble Shooting: If after you have placed the unit in the line by-passing the faulty circuit and the light on the trailer still does not work, it is either: a burned out bulb or the line on the trailer is severed. The Circuit Chaser will not fix either of these situations. It will also not replace the emergency or turn signal flashers. Circuit Chaser is fully guaranteed for one year against defective materials and workmanship.