There's some cheap & easy possibilities here, & some expensive ones. The first thing I'd check is make sure your hazard switch isn't partially on. Cycle it a couple times to make sure the switch is completely off. It only takes it being 1/8" on to make a little contact & screw all the lights up. Does the switch feel normal? Next turn on your left signal & go out & look at the lights. Are they the same brightness, or do you have a dim one? (bad socket, loose or corroded bulb, bad ground.) If it's none of these then it could be the TS switch, the hazard switch, or a fried relay, or wiring.
**I remember one post on here where there was dust/dirt/grime in the TS switch & the poster either blew it out with compressed air or some spray electrical cleaner & it fixed it.
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