Have you checked the flasher unit itself?

If everything is flashing quickly, might be a problem there. IIRC, most are thermally based and the internal element may have weakened over time. Any weird pops or clicks on the radio while this is happening (particularly in time with the signals)? Might be RFI being generated by the flasher.

Good Luck!

Jay

1991 Trooper - DEAD! 2.8 V6, 5 spd, 4WD, HD clutch, 2.25" exhaust, EPROM Chip, KC/Hella, Aisin hubs, Rancho 9000X's, Panasonic/Infinity/Alpine
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