Trailer Brake Controller Reads NC, No Trailer Connected, With or Without a Trailer Connected
Question:
2009 Nissan Frontier Crew Cab Controler was working then it just went to NC with the trailer connected. I have unplugged the brake controler and checked all wires and it still shows NC. Any suggestions. Thanks
asked by: Charles S
Expert Reply:
There are a coupler of reasons why a trailer brake controller, like # 90885, may be reading nc (no trailer connected) all the time. First and the easiest to check is the trailer and vehicle side connectors. If there is corrosion and/or dirt build up in or behind the connectors, that could be causing a bad connection or a short between the brake circuit and another circuit in the connector. Clean out any corrosion and dirt and see if that solves the issue.
If there is still a problem, you can check the brake controller wiring. Start with no trailer connected. Use a circuit tester like # PTW2993 if needed to test the wires behind the brake controller. Sever the blue wire behind the controller. Use the manual override. It should show a signal.
If there is a signal on the blue wire as there should be and there is no signal when you do not apply the manual override then the controller is working correctly. If it shows a signal on the blue wire when it should not, then something is wrong inside the controller and it will need to be replaced.
If the controller checks out and there is no corrosion or dirt in the connectors, then the issue is probably on the trailer side. You can first check the main ground for the trailer connector and the grounds for each brake magnet. They should be attached to clean and corrosion free metal surfaces. You can also check that the power wires for the magnets are intact and there are no exposed wires touching metal.
You can then move on to testing the brake magnets. Start by visually inspecting the magnets. If you can see the windings coming through the magnets will need to be replaced. To further test the magnets you will need a multimeter, like # PT89ZR, if needed. Follow the FAQ I have linked for you to test the magnets.
Products Referenced in This Question
Digital Multimeter with 42" Long Test Leads - LED Display
- Electrical Tools
- Testers
- Multimeter
- Yellow
- Performance Tool
more information >
Product Page this Question was Asked From
Tekonsha Prodigy P2 Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Electric over Hydraulic
- Automatic Leveling
- Under-Dash Box
- Dash Mount
- Up to 4 Axles
- LED Display
- Up to 360 Degrees
- Tekonsha
more information >
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