3rd brake light also has a lota green build up around LEDs
Dude, without a doubt its your 3rd brake light. It was a bid problem with the 2010's. happened to me and many others, same thing your describing, had mine replaced and haven't had a problem since.
Call your dealership, there was a TSB for it. Ill see if I can find it.
Hill Decent Control Fault. SSM 21317
Oasis special service message number: 21317
message title: 2010 svt raptor - hill decent control fault and dtc c116a
applicable vehicles :
2010 truck : 00029 f-series ld
oasis message :
Some 2010 f-150 svt raptor vehicles may exhibit hill decent control fault with
abs dtc c116a. On vehicles built before 2/26/2010 only, inspect the high mounted
stop lamp for evidence of
water intrusion. Refer to wsm section 417-01 for
replacement details part number al3z-13200-a. Torque screws to 1.5 nm / 13
lb-in. No
water intrusion follow wsm section 206-09, pin point test i. Note: It
is normal for the
brake pressure (brakpres) pid to occasionally spike high due
to test pulse sent to the pressure sensor by the abs module. In addition,
brake
pressure signals as low as -225 psi without
brake apply should also be
considered normal. .
Applicable symptom codes :
200000 electrical
206000 electrical warning indicators
300000 chassis
301000 chassis service
brake system