OBD II Fault Code B121B :

Description of Fault code B121B

A short in the mode control motor circuit

Possible failuer B121B

• Mode moter connect line short
• Mode moter potento line short
• Climate control unit internal 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

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: