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HVAC System DTCS

DTC B120A - B1241

DTC  Detection Item or Symptom  ECU  DTC Type 
B120A Climate Control Unit LIN Communication Bus Line Error Climate control unit Loss of communication
B1211 An Open in the ECOMP Circuit Climate control unit Signal error
B1212 An Open in the HVHTR Circuit Climate control unit Signal error
B121A An open in the mode control motor circuit Climate control unit Signal error
B121B A short in the mode control motor circuit Climate control unit Signal error
B121D Humidity/in-car temperature sensor communication error Climate control unit Loss of communication
B1220 A Short in the recirculation control motor circuit Climate control unit Signal error
B1231 An open in the evaporator temperature sensor circuit Climate control unit Signal error
B1232 A short in the evaporator temperature sensor circuit Climate control unit Signal error
B1233 An open in the air mix control motor circuit (driver's) Climate control unit Signal error
B1234 A short in the air mix control motor circuit (driver's) Climate control unit Signal error
B1235 A problem in the air mix control motor circuit, linkage, door, or motor (driver's) Climate control unit Signal error
B1236 An open in the passenger's air mix control motor circuit Climate control unit Signal error
B1237 A short in the passenger's air mix control motor circuit Climate control unit Signal error
B1238 A problem in the passenger's air mix control motor circuit, linkage, door, or motor Climate control unit Signal error
B123F Automatic lighting control unit/sunlight sensor error Climate control unit Signal error
B1240 A problem in the mode control motor circuit, linkage, door, or motor Climate control unit Signal error
B1241 A problem in the blower motor circuit Climate control unit Signal error
DTC B2964 - B2998

DTC  Detection Item or Symptom  ECU  DTC Type 
B2964 Climate control unit lost communication with Front PANEL Climate control unit Loss of communication
B296D Electric Heater Coolant Pump Communication Fail Climate control unit Loss of communication
B296E Electric Heater Coolant Pump Fail Climate control unit Signal error
B296F Electric Water Valve Fail Climate control unit Signal error
B2983 A problem in the recirculation control motor circuit, linkage, door, or motor Climate control unit Signal error
B2986 An open in the recirculation control motor circuit Climate control unit Signal error
B298A Electric Coolant Heater fail Climate control unit Signal error
B298B A/C Main Relay ON Fail Climate control unit Signal error
B2990 A problem in the A/C compressor driving circuit Climate control unit Signal error
B2996 An open in the heater core temperature sensor circuit Climate control unit Signal error
B2997 A short in the heater core temperature sensor circuit Climate control unit Signal error
B2998 A problem in the A/C compressor driver Climate control unit Signal error
DTC U0029 - U124A

DTC  Detection Item or Symptom  ECU  DTC Type 
U0029 F-CAN communication line error Climate control unit Loss of communication
U0100 Climate Control Unit Lost Communication With MG Module Climate control unit Loss of communication
U0180 Climate Control Unit Lost communication with automatic lighting control unit-sensor Climate control unit Loss of communication
U1207 Climate Control Unit Lost Communication With ECOMP Module Climate control unit Loss of communication
U1280 Communication bus line error (BUS-OFF) Climate control unit Loss of communication
U1281 Climate Control Unit Lost Communication with MICU Climate control unit Loss of communication
U128D Climate Control Unit Lost communication with gauge control module Climate control unit Loss of communication
U1290 Climate Control Unit Lost Communication With Seat Heater Control Unit Climate control unit Loss of communication
U12A4 Climate Control Unit Lost Communication With HVHTR Module Climate control unit Loss of communication