Troubleshooting Tuson DirecLink Brake Controller on 2009 Freightliner

Question:

I recently purchased a Tuson direclink for my 2009 freightliner and when I connect the trailer doesn’t detect the connection I tested the wires and I have 12 v on the black the red wire gets power when I press the brake and the blue wire gets signal when I press the override and when I pinch it with the tester is when I get the dash changing to connected why is this happening ? I am not sure if the trailer needs to be attached to the tractor in order to function

asked by: Juan C

Expert Reply:

Just to make sure I am understanding correctly, you are getting the correct signals on the black, blue, red, and white wires on the Tuson DirecLink, like the Base Model # 335DL-100, but when you connect your trailer to your 2009 Freightliner it doesn't receive a brake signal from the controller.

If this is the case then you simply need to test the wire that carries the brake signal from the controller back to your trailer. A typical 7-Way trailer connector should be receiving the brake controller signal on the pin in the 7 o'clock position (see attached image). Check to see if there are any places where the wiring is pinched or exposed and replace as necessary.

Let me know f this doesn't fix your issue or if the problem is something else and I can help you troubleshoot further.