Kenworth 07 T600 No turn signals????

Have the same truck. Gonna follow this as it could easily happen to anyone.

 

Did you check your fuses? Blown fuse or tripped breaker can do some funky things

 

And this is why the DOT has a job.

Your Krap is broken. Stop and fix it before you move one more mile

The broken damaged Krap I see truckin around 94-80 Blows me away

 

Did it fry the switch somehow?

 

I can help you on the LED headlight. We ran accross this accidentally. It was caused by getting the connector wet and energizing high beam power to low beam power at the same time. Gets them every time!! We’ve started coating the connectors (not the terminals) in dielectric grease to keep moisture out.
As for your blinkers, if your hazards are working then the flasher is probably fine. Is the blinker on the bumper a repair or is the bumper an added upgrade? Although there’s still a chance this is an unrelated issue that just happened at the same time, more than likely it’s coming from the area that was worked on. Crossing the turn and clearance circuits don’t normally cause a short or failed component. Usually just back feeding issues that cause things to work when they are not supposed to!!
First thing I would try is to disconnect any added or repaired lights and/or harness’ that may have been modified and see if the rest of the lights starts working again ( may have to wait a few minutes for a breaker to reset). If that doesn’t get you close then get out the test light and a creeper and set your beer down by your bible and start looking at schematics!!!!