Troubleshooting Curt Spectrum Brake Controller that Shows 3.4 Volts on Output at All Times
Updated 09/24/2019 | Published 09/23/2019 >
Products Featured in This Question
Question:
Ive hooked up the spectrum controller to my 2010 f150 and I get 12v when applying the brake into the controller. But for some reason it sends a constant 3.4v out to the 7pin. Brake pressed or not. I have running lights but no brake lights working..
asked by: Ray A
Expert Reply:
If you are getting a constant 3.4 volts on the brake output circuit of your brake controller without the brake pedal pressed that's a malfunction of the brake controller. Curt controllers are known to be a bit more prone to internal bugs so the first thing I would try is to unplug the controller for a few seconds to see if a hard reset fixes the issue. Here's how to test a brake controller completely to determine where the problem is:
Testing the brake controller is fairly easy. Sever the blue brake output wire near the brake controller leaving enough room to reconnect it and then apply the manual slide. Using a circuit tester like the Quickee Tester, part # PTW2993, you should get output to the controller side of the wire you severed. If the manual slide activates the trailer brake output wire properly, try the brake pedal. If the brake pedal activates the brake output properly also then the problem is farther back either in the vehicle wiring or on the trailer.
If either the brake pedal or the manual slide are not functioning properly you will need to test the wires going into the brake controller. Make sure you have power entering the brake controller on the black wire. On the red wire you will only want power when the brake pedal is pressed.
If there is power on the red wire before the brake pedal is pressed you have connected the red wire from the brake controller to the wrong circuit. You would then need to find the brake switch wire that has power ONLY when the brake pedal is activated.
If these connections check out and the brake controller is properly grounded then there is possibly a problem inside the brake controller.
I am including a link to a video that will show you how to test the wiring on a brake controller.
Product Page this Question was Asked From
Curt Spectrum Trailer Brake Controller - Dash Mounted Knob - Up to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Plug-In
- Dash-Mounted Knob
- Behind-Dash
- Up to 4 Axles
- Indicator Lights
- Multiple Trailers
- CURT
more information >
Featured Help Information
Instructions
Miscellaneous Media
Continue Researching
- Shop: Trailer Wiring
- Q&A: Troubleshooting Curt Spectrum Output and Sensitivity Adjustment
- Shop: etrailer Trailer Wiring 7-Way Upgrade Kit w/ Junction Box and RV Style Connector
- Video: etrailer 7 Way Upgrade Kit With Junction Box Installation
- Shop: Curt Dual Connection Socket w/ Bracket - 7-Way RV Style and 4-Way Flat - Vehicle End
- Q&A: How to Determine if Trailer 7-Way is Upside Down for Determining Pin Out
- Q&A: Will The Curt Spectrum Flash Blue When Brakes Are Pressed With No Trailer Attached.
- Q&A: Troubleshooting Installation of Curt Spectrum Brake Controller on 2011 Toyota Sienna
- Shop: Brake Controller
- Shop: etrailer Electric Trailer Brakes - 7" - Left/Right Hand Assemblies - 2,000 lbs
- Q&A: Replacement Brake Assemblies For A 2021 NuCamp TAG XL Teardrop Trailer
- Video: An In-Depth Look at the etrailer Electric Trailer Brakes
- Video: Trailer Brake Controller Wire Testing
- Shop: Curt Spectrum Trailer Brake Controller - Dash Mounted Knob - Up to 4 Axles - Proportional
- Q&A: Troubleshooting Solid Blue Light on Curt Echo Brake Controller
- Q&A: How Many Volts Should a Brake Controller Put Out on the Highest Gain
- Video: Checking Out the Replacement Magnet Kit for 7" Electric Trailer Brake Assemblies
- Article: Trailer Wiring Diagrams
- Search Results: trailer wiring
- Video: How to Choose a Trailer Brake Controller
- Shop: Trailer Hitch
- Shop: Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector
- Shop: Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Search Results: trailer hitch
- Video: What to Know About the Curt TriFlex NEXT Trailer Brake Controller
- Shop: Suspension Enhancement
- Video: Feature Breakdown: Universal Installation Kit for Trailer Brake Controller
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Shop: Redarc Tow-Pro Liberty Brake Controller w/ Universal Wiring Harness - Dash Knob - Proportional


