The Chrysler New Yorker Climate Control Module (ATC Automatic Temp Control Unit, part 3848576) is an integrated HVAC controller that manages temperature set‑points, fan speed, and compressor operation through a microprocessor and relays. Common failure modes include burnt or tripped relay contacts, failed MOSFETs causing loss of compressor control, capacitor degradation leading to erratic fan speeds, and corrupted firmware resulting in error codes such as “E01” (temperature sensor fault). First‑check diagnostics: verify 12 V power at the module’s input terminals; inspect all relays and MOSFETs for burn marks or cold solder joints; test temperature sensor wiring continuity and resistance against spec; and read any stored diagnostic trouble codes via the vehicle’s OBD interface.[oss-gpt-20b]