09KR0058

2010 F150 Lariat SCrew.

My left turn signal started fast-blinking today. Right side is normal. I assumed one of the bulbs was out, but after checking all 3 (front under headlight, driver side mirror and rear) all are working. Then checked the right side and they all work.

Am I missing something obvious?

NFortin1966

I do believe that the rear light has two bulbs, not one.

09KR0058

Correct, and both are working.

Now it gets stranger. Running some errands today and the left blinker is working normally. Let's see how long that lasts.

techrep

iTrader: (1)

Check the third brake light...

acdii

Easy fix, just need some of this

Ezerasurfr

Did you upgrade to LED at all? If you have, you may need a resistor. 50w6ohm to be specific

09KR0058

That still cracks me up

09KR0058

Negative. Thought about it, but never did and probably won't.

Summers22

iTrader: (2)

If it did it, then didn't there is surely an intermittent short somewhere.

RLXXI

I've experienced bulbs that were intermittent that could cause this issue, take each bulb out of socket and thump it with your finger, usually that will be enough to dislodge a filament that is hanging on by a literal thread.
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