About 2/3rds of the time my left front turn signal doesn't illuminate when the signal is engaged. The back left signal always flashes correctly though. When this happens the interior left signal light on the dash flashes irregularly and quickly.

Then the other 1/3rd of the the time, everything is normal. No warning lights and or anything. Battery is fully charged and on ctek when not driving regularly. Any ideas if its something simple? I'm planning on taking the car in soon to get brakes changed to ceramic and was going to ask the mechanic to take a look but if their is something simple I can do then why not.

 

Sounds like a chafed wire or a loose/corroded connector. The cable to the front left turn lamp runs from the auxiliary junction box (between the rear seats), and is black with a pink stripe, though I imagine it's probably buried in looms for much of its route.

 

I have the same problem with my 2012 XK. what was the resolution??