1997 Chevrolet Malibu

I have several lights staying on in my dash but yet no problems noticed. ABS and Brake lights, Battery light also. The Security alarm light comes on occasionally but usually goes off on next start up. No problems noticed with these lights on. This has been happening for about three months now. Also noticed is that the heat gauge doesn’t work at all and the AC doesn’t work either. Wiring and fuses have been looked at and no problems found. What is causing this?