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HVAC System DTCS

HVAC SYSTEM DIAGNOSTIC TROUBLE CODE (DTC) INDENTIFICATION

DTC  Detection Item or Symptom  DTC Type 
B121A An open in the mode control motor circuit Signal error
B121B A short in the mode control motor circuit Signal error
B1220 A short in the recirculation control motor circuit Signal error
B1225 An open in the in-car temperature sensor circuit Signal error
B1226 A short in the in-car temperature sensor circuit Signal error
B1227 An open in the outside air temperature sensor circuit Signal error
B1228 A short in the outside air temperature sensor circuit Signal error
B1229*2 An open in the sunlight sensor circuit Signal error
B1230*2 A short in the sunlight sensor circuit Signal error
B1231 An open in the evaporator temperature sensor circuit Signal error
B1232 A short in the evaporator temperature sensor circuit Signal error
B1233 An open in the air mix control motor circuit (driver's) Signal error
B1234 A short in the air mix control motor circuit (driver's) Signal error
B1235 A problem in the air mix control motor circuit, linkage, door, or motor (driver's) Signal error
B1236 An open in the passenger's air mix control motor circuit Signal error
B1237 A short in the passenger's air mix control motor circuit Signal error
B1238 A problem in the passenger's air mix control motor circuit, linkage, door, or motor Signal error
B123F*1 Automatic lighting control unit/sunlight sensor error Signal error
B1240 A problem in the mode control motor circuit, linkage, door, or motor Signal error
B1241 A problem in the blower motor circuit Signal error
B2964 Climate control unit lost communication with front panel (climate control panel) Loss of communication
B2967 An open in the humidity sensor circuit Signal error
B2968 A short in the humidity sensor circuit Signal error
B2983 A problem in the recirculation control motor circuit, linkage, door, or motor Signal error
B2986 An open in the recirculation control motor circuit Signal error
B2989 A problem in the A/C compressor motor (variable capacity control solenoid circuit) Signal error
U1280 Communication bus line error (BUS-OFF) Loss of communication
U1281 Climate control unit lost communication with MICU (body control module) Loss of communication
U128D Climate control unit lost communication with gauge control module Loss of communication
U1290 Climate control unit lost communication with seat heater control unit (front) Loss of communication

*1: Without automatic wiper

*2: With automatic wiper