A VOM is de regueur for most all red-blooded mal- -people. An FSM = better. Comb the stickies in Engine Prob/Maint. for the link to GOLDSSWAGON wiring diag. if you want to chase circuits. If you think you've got something way more complex than others, then add some background for more useful responses and suggestions. Are you using LEDs? Did you check EVERY bulb for proper function? The Hazards have their own flasher v. other lights - check that out. Was failure immediate one day, or gradually increasing episodes until permanent? Any other recent work especially electrical before this glitch?
\'96SS SOB: SSRI, Herter Tune, Tri-Y II, , 3000 Edge, F/HO bars, METCO extendeds with CV MMC, Bilsteins, currently Vredestein Ultrac Sessanta (315/35 rear). Finally, wait for it... LT-4 knock module!
\'96FWB BUW-Butt Ugly White: PCMPerformance tune, HDFA w/ swissed filter, 1/2 SLP s.s. catback with H- and Flow Super 50s, oem opti rebuilt 3 times, SS Bars, METCO LCA, Airlift 1000, Monroe SS, PowerTrax No-Slip, CTS wheels with +1 rubber. Finally, yes again... LT-4 knock module!