The OP's 2001 (as well as yours) uses a single electronic flasher. As suggested in an earlier post, there is no HD unit.I also would check the flasher. The directionals and the hazards use different/seperate flashers. If a new flasher (or just swap them with each other I think they are the same unit) doesnt work then I would tear into the multifunction switch as suggested above.
Hmmm. Only $78?If you isolate it to the multi-function switch, be sure to check the price at Napa. I got mine for only $78.