"suddenly after 5 years". The original battery?
I think ORradtech hit it with "weak battery".

 

battery was replaced at dealer year ago.... grips began to malfunction 6 months ago....i have to think something in that left grip contact is failing... ( maybe corroded ? ) will check with dealer saturday to see if that could indeed throw these 2 lights... lights have not come back on since i turned grips off and took another short ride yesterday afternoon.. thank u all for alawys helping out

 

My money is on a Voltage Regulator that has checked out. Mine did it the same way. Limped it home barely. J and P has an American made one that I put on and has been fine ever since. Also on a 2012 FLHTK

 

dealer says yes a faulty contact in the left grip could trigger a fault code and turn on both lights... turned off grips and they have been off since last week and lights have not come back on... will see in time... bike runs great...voltage holding steady at 12.5 at idle and 14 while cruising