This is the primary cause of trailer-light problems. Symptoms include flickering, fast-blinking, dimness, intermittent operation (often when a trailer ball is used for a ground), and complete failure.

Taillights get bounced around, dunked in the lake and soaked with road salt. So it’s no surprise that bulb filaments break and sockets corrode, causing a lot of lighting malfunctions. Sealed LED ...

Q:I am having a problem troubleshooting the trailer light plug on a 2002 Chevy Silverado. I get no power there. I've checked all the fuses and they're good. I expect it's a simple grounding problem, ...