What are B-codes?
B-codes relate to the body electronics of the vehicle, airbags and the supplemental restraint system (SRS), seat belt pretensioners, exterior lighting, climate control, windows, mirrors, and other comfort and convenience systems. Many B-codes have limited impact on drivability, though the airbag and seat belt codes are an important exception.
General context
B-codes related to airbags and the supplemental restraint system can affect whether occupant protection works as intended in a collision. Other B-codes typically affect comfort or convenience features. The actual impact of any specific B-code on a particular vehicle can only be confirmed by a qualified mechanic.
We don't assign per-code severity ratings. Whether a specific fault is urgent depends on the cause on a specific vehicle, which only a qualified mechanic can determine.
Most common B-codes
The B-codes drivers look up most often.
All B-codes (1,718)
Page 1 of 18 B0050 Driver Seatbelt Sensor (Subfault) B0052 Passenger Seatbelt Sensor (Subfault) B0053 Second Row Left Seatbelt Sensor (Subfault) B0054 Second Row Center Seatbelt Sensor (Subfault) B0055 Second Row Right Seatbelt Sensor (Subfault) B0056 Third Row Left Seatbelt Sensor (Subfault) B0058 Third Row Right Seatbelt Sensor (Subfault) B0059 Right Front/Passenger Pretensioner Deployment Loop Voltage Out of Range B0060 Driver Seatbelt Tension Sensor (Subfault) B0061 Passenger Seatbelt Tension Sensor (Subfault) B0090 Left Frontal Restraints Sensor (Subfault) B0091 Left Side Restraints Sensor 1 (Subfault) B0092 Left Side Restraints Sensor 2 (Subfault) B0093 Left Side Restraints Sensor 3 (Subfault) B0094 Center Frontal Restraints Sensor (Subfault) B0095 Right Frontal Restraints Sensor (Subfault) B0096 Right Side Restraints Sensor 1 (Subfault) B0097 Right Side Restraints Sensor 2 (Subfault) B0098 Right Side Restraints Sensor 3 (Subfault) B0099 Roll Over Sensor (Subfault) B009A Left Side Restraints Sensor 4 (Subfault) B009B Left Side Restraints Sensor 5 (Subfault) B009C Left Side Restraints Sensor 6 (Subfault) B009D Right Side Restraints Sensor 4 (Subfault) B009E Right Side Restraints Sensor 5 (Subfault) B009F Right Side Restraints Sensor 6 (Subfault) B00B0 Driver Seat Occupant Classification Sensor "A" (Subfault) B00B1 Driver Seat Occupant Classification Sensor "B" (Subfault) B00B2 Driver Seat Occupant Classification Sensor "C" (Subfault) B00B3 Driver Seat Occupant Classification Sensor "D" (Subfault) B00B4 Driver Seat Occupant Classification Sensor "E" (Subfault) B00B5 Driver Seat Track Position Restraints Sensor (Subfault) B00B6 Driver Seat Recline Position Restraints Sensor (Subfault) B00B7 Driver Seat Occupant Position Sensor "A" (Subfault) B00B8 Driver Seat Occupant Position Sensor "B" (Subfault) B00B9 Driver Seat Occupant Position Sensor "C" (Subfault) B00BA Driver Seat Occupant Position Sensor "D" (Subfault) B00BB Driver Seat Occupant Position Sensor "E" (Subfault) B00C0 Passenger Seat Occupant Classification Sensor "A" (Subfault) B00C1 Passenger Seat Occupant Classification Sensor "B" (Subfault) B00C2 Passenger Seat Occupant Classification Sensor "C" (Subfault) B00C3 Passenger Seat Occupant Classification Sensor "D" (Subfault) B00C4 Passenger Seat Occupant Classification Sensor "E" (Subfault) B00C5 Passenger Seat Track Position Restraints Sensor (Subfault) B00C6 Passenger Seat Recline Position Restraints Sensor (Subfault) B00C7 Passenger Seat Occupant Position Sensor "A" (Subfault) B00C8 Passenger Seat Occupant Position Sensor "B" (Subfault) B00C9 Passenger Seat Occupant Position Sensor "C" (Subfault) B00CA Passenger Seat Occupant Position Sensor "D" (Subfault) B00CB (definition pending) B00CC Passenger Seat Occupant Position Sensor "E" (Subfault) B1000 A/C Switch Request Input Circuit/Performance B1001 Multiplex Integrated Control Unit (MICU) Internal Error B1002 Multiplex Integrated Control Unit (MICU) Internal Error B1003 Panel Mode Switch Request Input Circuit/Performance B1005 MICU Lost Communication with Relay Control Module (RM Message) B1006 BI-Level Mode Switch Request Input Circuit/Performance B1007 MICU Lost Communication with Combination Switch Control Unit (HLSW Message) B1008 MICU Lost Communication With Gauge Control Module (A/T Message) B1009 Recirculation Switch Request Input Circuit/Performance B100A Recirculation Switch Request Input Circuit Low B100C Floor Mode Switch Request Input Circuit/Performance B100F Mix Switch Request Input Circuit Performance B1011 MICU Lost Communication with Gauge Control Module (VSP/NE Message) B1012 Defrost Switch Request Input Circuit/Performance B1013 MICU Lost Communication with Driver's MPCS Unit (ASLOCKSW Message) B1014 MICU Lost Communication With Driver's MPCS Unit (DOORSW Message) B1015 MICU Lost Communication with Driver's MPCS Unit (DRLOCKSW Message) B1016 MICU Lost Communication With Keyless Access Control Unit (PANIC Message) B1017 Airbag Occupant Sensing Control Unit B1019 Belt Tension Sensor B101D XX: ECU Hardware B101E Power On/Off Switch Request Input Circuit/Performance B1020 Airbag Occupant Sensing Control Unit B1021 Blower Speed Up Switch Request Input Circuit/Performance B1022 Occupant Sensor Control Unit Communication Failure B1023 SRS Passenger A/B Indicator Circuit B1024 Blower Speed Down Switch Request Input Circuit/Performance B1026 Passenger's Door Lock Switch Signal Error B1027 Trunk Key Cylinder Switch Signal Error B1028 Rear Blower Control Request Input Circuit Low B102E Rear Blend Request Input Circuit Low B102F Rear Blend Request Input Circuit High B1031 Evaporator Temperature Sensor Circuit Low B1032 MICU Lost Communication with the SRS Unit (CDS Message) B1033 Crash Zone Sensor B1034 Infrared Temperature Sensor Input Circuit Low B1035 Infrared Temperature Sensor Input Circuit High B1036 Infrared Sensor Period Too Long Or Too Short B1037 Auto Switch Request Input Circuit Performance B103A Rear Mode Door Control Circuit/Performance B103B Thermoelectric Driver Overcurrent Low B103D Rear Mode Door Control Circuit Open B1040 Panel Mode Door 1 Control Circuit/Performance B1041 Air mixing damper control motor and potentiometer (potentiometer system shorted to its power supply) B1042 Air mixing damper control motor and potentiometer (potentiometer system shorted to its ground) B1043 Panel Mode Door 1 Control Circuit Open B1046 Driver–Side Curtain Air Bag Module And Other Air Bag Module Circuits Short B1047 Driver-Side Side Air Bag Module And Other Air Bag Module Circuits Short B1048 Passenger-Side Air Bag Module (Inflator No.1) And Other Air Bag Module Circuits Short
Showing 1–100 of 1,716 remaining codes
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