I have a 2016 GMC. the fan on the AC comes on while engine is turned off
Are you sure it’s the AC fan? The cooling fan running after the engine is shut off is normal. I’ve never heard of that happening with the AC fan but I’d guess a bad ignition switch, maybe a faulty body control module.
Yes, absolutely! Went to dealer and they replaced the HVAC BLOWER RESISTER MOTOR. After $180 still have the same problem
Then go back to the dealer and tell their shop–nicely but firmly–that they haven’t fixed the problem and you want them to try again. $180 is a decent amount to spend and not fix the problem.