dtwbcs, If you have LED and have a stock Flasher. This is where the problem for you may be. Or at least start there.

There is a special Flasher unit for use with LED lights.

Poets Seat Auto
Appraisals, Parts, Service
Past: General Motor's Master Technician
Member: Northeast Chevy/GMC Truck Club
Phone Number: 413.774.5856
Collector of: 1951 Army Chevy Burb barn door,53 GMC COE,two 1934 Chevy Truck,1935 Chevy Army Truck.1950 Gmc Suburban clamshell these are just my chevy/gmc trucks.