Troubleshooting a 1995 D21 Air Conditioning Switch

I am seeking input on troubleshooting our 1995 D21 A/C which stopped working and may be attributed to either:
1. Belt coming off and sticking under crankshaft pulley. Or
2. Possible damage to switch when trying to fix blower settings.
Any feedback is greatly appreciated. Thank you for watching.
#a/c #airconditioning #diy #1995 #D21 #acrepair #auto