Question Was Asked By - Jim H

Measuring the Voltage Output of a Brake Controller

Question:

Can you test the power that operates the brakes on the trailer,from the 6 pin connector on back of truck? I would think the harder you push the brake petal,the more volts or amps youd have.I cant tell if the brake controler is working right.If I could check the voltage or amps,Id know if its working.

asked by: Jim H

Expert Reply:

There are two different types of brake controllers, time-delayed and proportional. A time-delayed controller will always send the same amount of voltage according to how the controller has been set. The amount of time between the brakes being applied in the vehicle and the actuation of the trailer brakes can also be adjusted. A proportional controller will sense how quickly, and at what intensity the tow vehicle is stopping, and send the proper amount of voltage to the trailer brakes so that the vehicle and trailer stop at the same rate. For a time-delayed controller, if the output is turned all the way up, you should read close to 12V at the trailer connector when the brakes are applied or the override switch is activated. A proportional controller will not actuate by pressing the brake pedal unless the vehicle is in motion. You can test the output at the connector by activating the manual override switch. With the power turned up to maximum, once again you should read nearly 12V.

expert reply by: Mike L

Products Referenced in This Question

Circuit Tester Kit