The problem with the scenario described by our driver is that a bad battery will not effect the winch operation on a trailer equipped with electronic brakes. Although is on the same circuit as the winch, the battery is part of the emergency braking system and not critical to the operation of the winch. This driver’s problem was in his wiring and not the battery.
“But I never unhooked and the winch worked fine yesterday,” the driver claimed. And we believe him.
Under difficult winter conditions when equipment is exposed to water and road salts, corrosion erodes connections quickly, making wiring maintenance almost a weekly issue.
Water seeps inside plug connections and even when the contacts are treated with dielectric grease corrosion will occur inside the plug causing the connections to fail. In the picture above the red wire is the power supply to the truck’s winch. When that connection fails the winch will run for a short period powered by the battery, then stop when the battery is dead.
The connection shown above was completely clean in November, and the corrosion occurred in only about 6 weeks of winter operations. A weekly inspection of wiring connections and a light coat of WD40 will slow the corrosion inside the plug.