How to Determine Which Wire is the Stoplight Circuit for a Brake Controller on a 2007 Honda CR-V

Question:

When connecting to the brake light switch I see two thin wires about 26-28 guage - white - joined together and a single darker possibly black wire looks like about a 22 guage coming from the switch. Do you know which wires I should tie the controllers red wire to? Is it one of the two white wires or the larger black wire?

asked by: Mac Y

Expert Reply:

To determine which wire to use from your 2007 Honda CR-V for the red stoplight circuit from your brake controller you should use a circuit tester # PTW2993 to test the wires for voltage when the brake is applied and then no voltage when the brake is not being applied.

Once you find the wire that meets that criteria you have found the wire you should connect to the red stoplight circuit of your controller.

I attached a video of the # PTW2993 in action.

expert reply by: Jameson C