Rapid directional flashing solved (1st Gen)

[DeRocha]

My directionals either side were beginning to flash very rapidly (so fast the bulbs would NOT illuminate). However the bulbs flashed correctly if I stepped on the brakes or I used the hazard lights. I search the boards and found many issues related to the multi-function controller and a few mentioned trailer wiring (which I suspected). I had a 2" brake light (below) plugged into my receiver hitch and noticed some corrosion on the plug connectors. I remove the brake light and the directions worked fine... The corrosion (due to the severe New England winter) was causing the terminals to short with one another causing the problem.

 

[V8BoatBuilder]

My third brake light sometimes becomes intermittant, due to corrosion/gunk in the trailer harness as well.

 

[Creager]

intresting my 92 was doing that for a month or so. But it seemed to had fixed itself, i dont know what the problem was. Probably exacly what you said, corrosion.