Controls System - HVAC System - Electronic

IMPORTANT: If Heater/Vent/Air Conditioning (HVAC) Control Head and/or Programmer appear completely inoperative, refer to A/C System Check, and perform Chart #2 on before proceeding. Chart 2 HVAC Control Head and/or Programmer Inoperative

Diagnosis for this system is based on Diagnostic Trouble Codes (DTCs) stored in the HVAC Control Head. When a DTC has been stored the MODE Indicator (LED) of the current mode will flash. Three dashes will be displayed on the HVAC Control Head if the Programmer fails.