Troubleshooting A Curt Discovery NEXT Brake Controller That Is Manually Activating On Its Own
Updated 01/05/2026 | Published 09/16/2024 >
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Question:
I recently bought a Curt Discovery braker controller from your site. when I installed it, I discovered that the controller is back feeding power to the breaks when they are not applied. When the trailer is hooked up it shows the M for manual mode when it is not being activated.
asked by: Kevin O
Expert Reply:
Hi Kevin,
If 'M' is showing up on your Curt Discovery NEXT Brake Controller # C38SV then that means the manual override is being activated. Is it giving you a number with that or just 'M'? I would check to see if your manual override switch might have something stuck in the spring/hinge preventing it from rebounding back out when not in use. If you slightly pull out on it does the M go away?
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etrailer Rubber Hitch Cover for 2" Trailer Hitches - Qty 1
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Robin H.
1/5/2026
Hey Kevin, did pulling out on the manual override switch clear the “M” on your Curt Discovery brake controller? Your update could make it easier for others who see the same issue.