How to Adjust Electric Brake Controllersby Thomas West
An electric brake controller is a necessary safety feature when towing a heavy trailer. Expecting your tow vehicle to provide all of the braking needed to stop the entire rig may be asking for trouble. An electric brake controller installed in your tow vehicle applies the trailer brakes automatically when the tow vehicle's brakes have been applied. Most brake controllers will apply only the amount of braking needed, depending on speed, the amount of pressure applied to the brake pedal and the rate of deceleration. If your electric brake controller is not adjusted properly, the trailer brakes may grab, skid or not work at all.
Connect the trailer to the tow vehicle. Plug in the trailer's electrical connection to the receptacle near the trailer hitch on the rear of the tow vehicle.
Warm the trailer brakes by driving the rig at 45 mph with the manual lever on the brake controller applied for approximately ¼ mile. Tow the rig to a paved area that is flat and dry, such as a parking lot or deserted street or road.
Keep the engine running. Turn the power control knob on the brake controller to its mid-point setting.
Drive the rig up to a speed of approximately 25 mph and release the accelerator.
Slide the manual control lever on the front of the brake controller all the way over to its maximum limit.
Note the braking action of the trailer. If the trailer wheels locked up or skidded on the pavement, turn the power lever down to the next setting. If trailer braking was not sufficient to slow down the entire rig, turn up the power knob to its next setting.
Repeat the driving and braking test and make adjustments as necessary. Continue to make adjustments until trailer wheel-skid has been eliminated and there is sufficient trailer brakes to slow the entire rig down noticeably.
Test-drive the rig again and use the tow vehicle's brake pedal to slow or stop the rig. Make further finetune adjustments to the power knob on the brake controller, if necessary, until you are comfortable that the trailer brakes are doing their share of slowing and stopping the rig without grabbing or skidding.
- The trailer brakes may need to be adjusted with the power knob on the brake controller when the weather or weight of the trailer load changes. A reduction in braking power may be needed when roads are slippery, and an increase in power may be needed when the load is heavier.