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HVAC System DTCS

HVAC SYSTEM DIAGNOSTIC TROUBLE CODE (DTC) INDENTIFICATION

DTC  Detection Item or Symptom  ECU  DTC Type 
U1280 Communication bus line error (BUS-OFF) Climate control unit Loss of communication
U1281 Lost Communication with MICU (climate control unit) Climate control unit Loss of communication
U128D - Refer to: DTC Troubleshooting: (U128D (D-A2) (Without Auto Idle Stop System) (2014 2015 2016 2017 2018 2019 2020) or DTC Troubleshooting: U128D (D-A2) (With Auto Idle Stop System) (2016 2017 2018 2019 2020) Lost communication with gauge control module (climate control unit) Climate control unit Loss of communication
U1290 - Refer to: DTC Troubleshooting: U1290 (D-B3) (2014 2015) or DTC Troubleshooting: U1290 (D-B3) (Without Auto Idle Stop System) (2016 2017 2018 2019 2020) or DTC Troubleshooting: U1290 (D-B3) (With Auto Idle Stop System) (2016 2017 2018 2019 2020) Lost communication with seat heater control unit (front) (climate control unit) Climate control unit Loss of communication
U129B - Refer to: DTC Troubleshooting: U129B (D-B4) (Climate Control Unit (Without Auto Idle Stop System) (2014-20) or DTC Troubleshooting: U129B (D-B4) (With Auto Idle Stop System) (2016 2017 2018) Lost communication with seat heater control unit (second row seat) (climate control unit) Climate control unit Loss of communication
B1213 An open in the rear evaporator temperature sensor circuit Climate control unit Signal error
B1214 A short in the rear evaporator temperature sensor circuit Climate control unit Signal error
B1220 A short in the recirculation control motor circuit Climate control unit Signal error
B1221 An open in the rear mode control motor circuit Climate control unit Signal error
B1222 A short in the rear mode control motor circuit Climate control unit Signal error
B1223 A problem in the rear blower motor circuit Climate control unit Signal error
B1225 An open in the in-car temperature sensor circuit Climate control unit Signal error
B1226 A short in the in-car temperature sensor circuit Climate control unit Signal error
B1227 An open in the outside air temperature sensor circuit Climate control unit Signal error
B1228 A short in the outside air temperature sensor circuit Climate control unit Signal error
B1229 An open in the sunlight sensor circuit Climate control unit Signal error
B1230 A short in the sunlight sensor circuit Climate control unit Signal error
B1231 An open in the evaporator temperature sensor circuit (front) Climate control unit Signal error
B1232 A short in the evaporator temperature sensor circuit (front) 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 - Refer to: DTC Troubleshooting: B1235 (B-A3) (2014 2015 2016) A problem in the air mix control motor circuit, linkage, door, or motor (driver's) Climate control unit Signal error
B1236 - Refer to: DTC Troubleshooting: B1236 (B-A4) (2014 2015 2016) An open in the passenger's air mix control motor circuit Climate control unit Signal error
B1237 - Refer to: DTC Troubleshooting: B1237 (B-A5) (2014 2015 2016) 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
B1241 A problem in the blower motor circuit (front) Climate control unit Signal error
B1244 An open in the rear air mix control motor circuit Climate control unit Signal error
B1245 A short in the rear air mix control motor circuit Climate control unit Signal error
B1246 A problem in the rear air mix control motor circuit, linkage, door, or motor Climate control unit Signal error
B1248 A problem in the rear mode control motor circuit, linkage, door, or motor Climate control unit Signal error
B2965 - Refer to: DTC Troubleshooting: B2965 (E-A7) (Without Auto Idle Stop System) (2014 2015 2016) or DTC Troubleshooting: B2965 (E-A7) (With Auto Idle Stop System) (2016) Rear communication failure Climate control unit Loss of communication
B2967 - Refer to: DTC Troubleshooting: B2967 (F-A3) (2014 2015 2016) An open in the humidity sensor circuit Climate control unit Signal error
B2968 A short in the humidity sensor circuit Climate control unit Signal error
B2969 An open in the mode control motor A circuit (front) Climate control unit Signal error
B2970 A short in the mode control motor A circuit (front) Climate control unit Signal error
B2971 A problem in the mode control motor A circuit, linkage, door, or motor (front) Climate control unit Signal error
B2972 An open in the mode control motor B circuit (front) Climate control unit Signal error
B2973 A short in the mode control motor B circuit (front) Climate control unit Signal error
B2974 A problem in the mode control motor B circuit, linkage, door, or motor (front) Climate control unit Signal error
B2979 An open in the A/C pressure sensor circuit Climate control unit Signal error
B2980 A short in the A/C pressure sensor circuit 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