2011 f150 Still have blinker issue. Replaced front and rear bulb and I'm still having the fast blinker issue. I can hear he relay clicking the same speed as the fast blinker. I swapped in another relay and nothing changed.

 

The rear tail lamp has 2(two) bulbs.
.

 

all bulbs are new on that side even the bulb in the mirror

 

Did you put in LEDs?

 

nope. All stock

 

I had a issue similar to this on my 2003 F150 years back. Its turned out to be the multifunction switch was bad.

Wayne