1999 Dyna wide glide carbureted.

At power up , engine light comes on and extinguishes after 4 seconds, but then comes back on after another 4 seconds. Harley dealer ran the codes and no faults found. I tried another speedo and same,
. I tried ignition module, cam and crank sensors and still same. Bike starts and runs and drives great...just the engine light. Ran the scanner again after about 50 miles and same no faults found.
Any ideas???