Front drivers side turn signal. Light works but wont flash when you turn on the signal.

[Huckleberry]

1978 GMC. K15. Front marker light won't flash when you put on turn signal. All other lights work correct.

 

[rancher1913]

check ground and also check that somebody did not stick an led buld in it, they need a special flasher control

 

[78C10BigTen]

A burnt out bulb??

 

[mlsceo]

Probably just a bad ground. When mine does that I give the fender a tap with my fist and it goes right back to flashing.