New member to the forum here.
I have a 2013 sonata. Recently I replaced the steering coupler. About two or so days later my HVAC system entirely stopped working, it’s like it’s not receiving any type of power. Also my windshield wipers stopped working.

I’ve checked and replaced all the fuses and relays and have had no change.

Next to taking everything back apart, Does anyone have any ideas on what the issue may be? I guess maybe a harness came loose, but what harness would control the windshield wipers and heat controls?

 

I would suggest you check for a loose, corroded ,or missing ground wire to the firewall or sheet metal of the vehicle.
Both of those functions could share the common ground.