Troubleshooting Tekonsha Prodigy Showing 2 Dots With 5th Wheel Trailer Connected

Question:

Hi, I have a problem with my electrical connection . When checking the circuit in the Blue Wire coming from the Tekomsha Protigy P2 brake connector to the point where it disappears into the trailer 5th Wheel there is power. There are 2 dots showing at the Brake connector. What could be the problem? Thank you,

asked by: Dieter N

Helpful Expert Reply:

Wiring problems are always interesting because one little bit of exposed wiring can cause multiple different problems.

What I recommend that you start off doing is using a 12V battery (you can just use the one in your truck) to apply 12V power directly to the pin for the brake controller. This will be the pin in the 7 o'clock position on your trailer's 7-Way connector (see attached picture). If the trailer brakes do not activate (there should be a little hum) then you know that the problem is on your trailer. You will then want to test your brakes themselves by cutting the 2 wires connected to your brake assembly and applying that same 12V power to the brakes. If they activate using this method then you know for sure that there is a problem with the wiring between the 7-Way connector and your brakes.

If this is the case then you have a few different options.

You can either search your 5th wheel trailer for the wiring and once it is found look for any places that are damaged, exposed, bent, or corroded and replace them with 10 Gauge Wire # 10-1-1 and Butt Connectors # DW05745-5.

You can also just run your own wiring using the wire and butt connectors I just mentioned. I have attached a helpful article about wiring for this option.

You can just take the trailer to a shop and have them check it out.

If when you apply 12V power to the trailer 7-Way connector the brakes on your trailer do activate then you know the problem is on your truck side. You can use a Circuit Tester # PTW2992 to make sure that the 7-Way connector on your truck is getting the proper power and if it isn't you can follow the same wire troubleshooting steps that I just mentioned for your trailer. You might even need to replace wiring from your Tekonsha Prodigy P2 # 90885 to the 7-Way connector on your truck.

If neither of these options work then you will want to take your whole setup (truck and trailer) to a qualified mechanic who can physically inspect it.