I been jacking with boat trailer lights and finally bought and installed the complete LED submersible kit and all brand new including a good ground. The trailer lights worked fine and the truck lights behaved normal. Now today, with the trailer harness unplugged, the right blinker goes at double speed. The bottom light on the right rear isn’t blinking. I have to pull that boat home 300 miles in the morning and running out of time to finish getting stuff done. I probably shorted something out when testing the old wiring or new before I crimped on the Connectors. Is this likely to cause me trouble on the way home if I don’t fix it tonight? I’m guessing a simple bulb change but every extra thing to do adds up and I gotta lot left to do. 2012 F 150.

Fuse Bulb

You probably have a blown bulb. Most of the time I find them blown in the rear.

Bulb

when mine flashes fast it is the bulb

Bulb, easy fix.

Blinker AIDS?

Low fluid

Blinker fluid is low.

I checked the level and added about a pint but that didn’t fix it.
Glad we now know it’s the bulb.
I was thinking about waiting till I get home to fix it.
I know, simple fix. Should be a 5 min job for most people. Sometimes I blow the curve right off the chart on simple fixes.

Hate trailer lights, kicking trailer seems to get them working.

A good cussing usually gets done also. Neither one seems to work for me. Ripping out, guts feathers and all then replacing with all new usually is the final fix. This one now has a 14 ga. solid for the ground. Attached 2 places to the trailer frame. Bad ground was the start of the problem but only the running lights would work. Halfazzed worked
But the whole shooting match was a intermittent mess. First thing I did with the new kit was throw away those damn guillotine pliers activated connectors.

Ok so the guy at autozone sold me a pair of 4057 bulbs after we confirmed it was 2012 f150 xlt rear turn signal.
They looked sort of familiar so I looked in the door pocket and sure enough there was one left in the 2 pack from last time this happened. Except they were 3057. Both look identical and say Sylvania Longlife which is apparently a little over 2 years. Any idea what’s up with the 2 different part numbers?

Judging from the bulb socket I reckon this one got a little warm somewhere along the way.

It is a low current condition causing the old school flasher to blink fast. You will see this when replacing incandescent bulbs with LED bulbs (which is a good thing). The LED bulbs draw very little current (and last forever) which will cause the hyperflash to occur.

Simply replace the old flasher with a solid state flasher and hyperflash is history. You can then run any combination of bulb types without issue, but you do lose the bad bulb detection. No biggie if you run LED as they almost never quit working and will not burn up the sockets which is another problem you have.