edgreenberg

Unfortunately, the end result is that I gave it to a local RV shop that does brake controllers regularly. I was unable to get under the dash to look for the stoplight switch to trace the wires. As I said in an earlier post, I'm pretty sure that it's either a wiring problem to the brake light switch or it needs a brake controller. We'll see what the mechanic finds. Thank you all for your suggestions and information. I understand a lot more now. That still doesn't help me get under the dash :-)

Thanks for both answers.  My problem is that I can apply the brakes with the manual handle, but I don't think I'm getting any braking from applying the truck brakes.  I suspect one of two things:

• The brake (light) switch voltage is not reaching the brake controller
• The brake controller's pendulum is not indicating that I'm slowing down. 

I believe that the connection from the controller to the seven pin connector is good, since I can manually brake, and I think that you've set me on a good troubleshooting path. 

Thanks

Hi, quick question.  If placing a voltmeter on the output of the seven pin trailer connector, is the brake circuit a steady 12 volts, or is it a variable voltage in proportion to braking desired?