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OBD II Fault Code B121C :

Description of Fault code B121C

Aircon Inverter communication Error

Possible failuer B121C

  • Climate Control Unit communication line open
  • Inverter communication line short
  • Inverter failure

Diagnostic Procedure using AutoHex II Scan Tool

  • The built-in diagnostic data in the EEPROM internal conflicts.
  • Reading the data from the EEPROM is abnormal.
  • Writing the data from the EEPROM is abnormal.
  • When the message of the EEPROM is judged as wrong, the predetermined alternative value is output.

Test Conditions using AutoHex tester

  • During the access to the EEPROM

Clear Fault codes Conditions

  • The built-in diagnostic data in the EEPROM internal conflicts.
  • Reading the data from the EEPROM is abnormal.
  • Writing the data from the EEPROM is abnormal.
  • When the message of the EEPROM is judged as wrong, the predetermined alternative value is output.

MIL Status

  • Check Engine Light ON

Programming BMW F Series


Note:

  • AutoHex II is a professional Auto diagnostic.
  • This fault code is a GERENRIC fault code, some cars may change the meaning of this fault code.
    To get the accurate fault code description you may use AutoHex II

More Fault codes:

OBD II Fault Code B121D
OBD II Fault Code B121E
OBD II Fault Code B121F
OBD II Fault Code B1220
OBD II Fault Code B1221
OBD II Fault Code B1222
OBD II Fault Code B1223
OBD II Fault Code B1224
OBD II Fault Code B1225
OBD II Fault Code B1226
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