How do you fix a heater control on a Chevrolet 1992 K1500 - the clock is stuck at 100 the radio don't work and the heater-AC controls won't light up?

To fix the heater control on a 1992 Chevrolet K1500, start by checking the fuse related to the HVAC system, as a blown fuse can cause multiple electrical issues. If the fuse is intact, inspect the wiring harness behind the control panel for any loose connections or damage. You may also need to replace the entire control unit if it is faulty. Lastly, ensure that the battery is in good condition, as low voltage can affect multiple electronic components in the vehicle.