This guide provides a detailed breakdown of B-Codes (B00E1-B00E8), which pertain to Body Control Module (BCM) and Occupant Detection System (ODS) faults in modern vehicles. These codes typically involve:
-
- Seat weight/position sensors (B00E1-B00E6)
- Airbag/occupant classification system (B00E5, B00E8)
- Calibration/data errors (B00E4, B00E7)
Impact:
-
Critical codes (e.g., B00E5) may disable airbags, requiring immediate attention.
High-priority codes affect safety systems (e.g., faulty seat sensors).
Medium-priority codes may cause incorrect airbag deployment but aren’t immediate failures.
Use Case:
Helps technicians diagnose issues with passenger detection, seat sensors, and airbag readinesswhile prioritizing repairs based on severity.
Key Features of This Guide:
-
- Color-Coded Severity Levels – Quickly identify urgent vs. non-urgent repairs.
- Clear Descriptions – Explains what each code means in plain terms.
- Possible Causes – Lists common faults (wiring, sensor failure, calibration errors).
- Actionable Insights – Recommends fixes like sensor replacement or system recalibration.
Ideal For: Automotive technicians, DIYers, and service manuals needing a concise B-Code reference.
Body Control Module (BCM) DTC Reference Table
(Color Key: Critical | High | Medium | 
Low)
| DTC Code | Severity | Description | Possible Causes |
|---|---|---|---|
| B0001 | High |
Driver Frontal Stage 1 Deployment Control | Faulty airbag, wiring issue, impact sensor malfunction |
| B0002 | Critical |
Driver Frontal Stage 2 Deployment Control | Airbag circuit failure, SDM module fault |
| B0003 | High |
Passenger Frontal Stage 1 Deployment Control | Occupant sensor fault, wiring harness issue |
| B0004 | Critical |
Passenger Frontal Stage 2 Deployment Control | Airbag module failure, crash sensor error |
| B0005 | High |
Driver Knee Bolster Deployment Control | Knee airbag circuit fault, connector issue |
| B0010 | Critical |
Passenger Side Deployment Control (Stage 1) | Side impact sensor failure, wiring short |
| B0011 | Critical |
Passenger Side Deployment Control (Stage 2) | Airbag inflator fault, module communication error |
| B0012 | High |
Driver Side Deployment Control (Stage 1) | Seat harness issue, impact sensor fault |
| B0013 | Critical |
Driver Side Deployment Control (Stage 2) | Side airbag circuit failure, SDM fault |
| B0020 | High |
Left Curtain Deployment Control (Stage 1) | Curtain airbag connector issue, wiring fault |
| B0021 | Critical |
Left Curtain Deployment Control (Stage 2) | Airbag inflator failure, module configuration error |
| B0022 | High |
Right Curtain Deployment Control (Stage 1) | Roof rail sensor fault, wiring damage |
| B0028 | Medium |
Seat Belt Pretensioner Deployment Control (Left) | Pretensioner circuit fault, connector corrosion |
| B0029 | Medium |
Seat Belt Pretensioner Deployment Control (Right) | Pretensioner squib resistance out of range |
| B002A | High |
Center Curtain Deployment Control | Sensor misalignment, wiring short to ground |
| B0030 | High |
Seat Occupant Detection System Fault | Weight sensor failure, mat sensor damage |
| B0031 | Medium |
Passenger Presence System (PPS) Fault | Faulty PPS module, calibration required |
| B0032 | High |
Child Seat Detection System Malfunction | Sensor contamination, wiring issue |
| B0033 | Medium |
Occupant Classification System Error | System calibration needed, sensor fault |
| B0038 | High |
Side Impact Sensor (Left Front) Communication Fault | Sensor unplugged, CAN bus communication error |
| B0039 | High |
Side Impact Sensor (Right Front) Communication Fault | Wiring damage, sensor internal failure |
| B003A | High |
Side Impact Sensor (Left Rear) Communication Fault | Connector issue, sensor misalignment |
| B003B | High |
Side Impact Sensor (Right Rear) Communication Fault | Power supply issue, sensor configuration error |
| B0040 | Critical |
Restraints Control Module Internal Fault | Internal SDM failure, requires replacement |
| B0041 | Critical |
Restraints Control Module Configuration Error | Incorrect programming, software version mismatch |
| B0042 | High |
Restraints System Voltage Low | Charging system fault, low battery voltage |
| B0043 | High |
Restraints System Voltage High | Alternator overcharging, voltage regulator fault |
| B0048 | High |
Driver Seat Position Sensor Fault | Sensor unplugged, wiring harness damage |
| B0049 | High |
Passenger Seat Position Sensor Fault | Sensor calibration needed, mechanical binding |
| B004A | Medium |
Driver Seat Belt Buckle Switch Fault | Switch failure, wiring short to ground |
| B004B | Medium |
Passenger Seat Belt Buckle Switch Fault | Connector issue, switch internal failure |
| B0050 | High |
Driver Airbag Squib Circuit Open | Clock spring failure, wiring break |
| B0051 | High |
Driver Airbag Squib Circuit Short to Ground | Wiring harness damage, airbag connector corrosion |
| B0052 | High |
Driver Airbag Squib Circuit Short to Battery | Wiring short to power, module fault |
| B0053 | High |
Driver Airbag Squib Circuit Resistance Low | Faulty airbag, incorrect component installed |
| B0054 | High |
Driver Airbag Squib Circuit Resistance High | High resistance in circuit, poor connection |
| B0055 | High |
Passenger Airbag Squib Circuit Open | Connector unplugged, wiring break |
| B0056 | High |
Passenger Airbag Squib Circuit Short to Ground | Wiring harness damage, airbag fault |
| B0057 | High |
Passenger Airbag Squib Circuit Short to Battery | Short to power, module internal fault |
| B0058 | High |
Passenger Airbag Squib Circuit Resistance Low | Faulty airbag, incorrect component |
| B0060 | High |
Left Side Airbag Squib Circuit Open | Wiring break, connector issue |
| B0061 | High |
Right Side Airbag Squib Circuit Open | Harness damage, airbag connector fault |
| B0070 | Critical |
Driver Seatbelt Sensor Circuit Malfunction | Faulty sensor, wiring short/open, BCM issue |
| B0071 | Critical |
Passenger Seatbelt Sensor Circuit Malfunction | Sensor failure, damaged wiring, poor connection |
| B0072 | High |
Left Side Impact Sensor Circuit Low Voltage | Low power supply, sensor fault, wiring issue |
| B0073 | High |
Left Side Impact Sensor Circuit High Voltage | Short to power, sensor failure |
| B0074 | High |
Right Side Impact Sensor Circuit Low Voltage | Wiring fault, poor ground, sensor malfunction |
| B0075 | High |
Right Side Impact Sensor Circuit High Voltage | Short to battery, sensor defect |
| B0076 | Critical |
Front Impact Sensor #1 Circuit Malfunction | Crash sensor failure, wiring damage |
| B0077 | Critical |
Front Impact Sensor #2 Circuit Malfunction | Sensor misalignment, communication error |
| B0078 | High |
Airbag Squib Circuit (Driver Side) Open | Broken clock spring, wiring break, faulty airbag |
| B0079 | High |
Airbag Squib Circuit (Passenger Side) Open | Disconnected connector, airbag fault |
| B007A | High |
Side Airbag Circuit (Left) Resistance Low | Short circuit, damaged squib |
| B007B | High |
Side Airbag Circuit (Right) Resistance High | High resistance in wiring, poor connection |
| B007C | Critical |
Seat Occupancy Sensor Circuit Malfunction | Faulty sensor, wiring issue, BCM error |
| B007D | Medium |
Seat Position Sensor Circuit Range/Performance | Sensor misalignment, calibration needed |
| B007E | High |
Pedestrian Impact Sensor Signal Invalid | Sensor damage, wiring fault |
| B007F | High |
Restraint System Communication Bus Off | CAN bus fault, module failure |
| B0080 | Critical |
Airbag Deployment Commanded | Crash detected, system locked (post-accident) |
| B0081 | High |
Airbag Disabled Indicator Circuit Malfunction | Faulty indicator, wiring short |
| B0082 | High |
Seatbelt Pretensioner Circuit (Driver) Open | Pretensioner fault, wiring break |
| B0083 | High |
Seatbelt Pretensioner Circuit (Passenger) Short | Short to ground, pretensioner failure |
| B0084 | Medium |
Roof Airbag Circuit Resistance Out of Range | High resistance, connector corrosion |
| B0085 | High |
Knee Airbag Circuit (Driver) Malfunction | Wiring issue, airbag fault |
| B0086 | High |
Knee Airbag Circuit (Passenger) Malfunction | Short circuit, squib failure |
| B0087 | Medium |
Seatbelt Buckle Switch Circuit Invalid Signal | Faulty switch, misalignment |
| B0088 | High |
Restraint System Power Supply Low Voltage | Weak battery, faulty power supply circuit |
| B0090 | Critical |
SRS Warning Lamp Circuit Malfunction | Bulb failure, wiring short, BCM issue |
| B0091 | High |
Event Data Recorder Communication Error | EDR module fault, CAN bus issue |
| B0092 | High |
Passenger Airbag Disable Switch Circuit Fault | Switch failure, wiring short/open |
| B0093 | Medium |
Child Seat Detection Sensor Circuit Malfunction | Sensor dirty, wiring issue |
| B0094 | High |
Occupant Classification System (OCS) Error | Faulty OCS sensor, calibration needed |
| B0095 | Critical |
Restraint System Configuration Mismatch | Incorrect module programming, replaced parts |
| B0096 | High |
Crash Data Stored (Non-Deployment Event) | Minor impact detected, system requires reset |
| B00A0 | High |
Seatbelt Anchor Pretensioner Circuit Fault | Pretensioner failure, wiring issue |
| B00B0 | Medium |
Left Side Impact Sensor Communication Error | Loose connector, sensor fault |
| B00B1 | Medium |
Right Side Impact Sensor Communication Error | Wiring damage, sensor malfunction |
| B00C0 | High |
Airbag Module (Driver) Internal Fault | Internal short, module replacement needed |
| B00D0 | High |
Restraint System Sensor Power Supply Fault | Blown fuse, wiring short |
| B00E0 | Critical |
Restraint System ECU Hardware Failure | Internal ECU fault, requires replacement |
| B00E1 | High |
Occupant Classification System (OCS) Sensor Malfunction | Faulty OCS sensor, wiring issue, seat mat damage |
| B00E2 | High |
Passenger Seat Weight Sensor Circuit Low | Short to ground, sensor failure, poor connection |
| B00E3 | High |
Passenger Seat Weight Sensor Circuit High | Short to power, sensor fault, wiring damage |
| B00E4 | Medium |
Occupant Classification System Calibration Error | Incorrect calibration, sensor misalignment |
| B00E5 | Critical |
Occupant Detection System Failure (Airbag Light ON) | OCS module failure, wiring fault, BCM error |
| B00E6 | High |
Passenger Seat Position Sensor Circuit Malfunction | Sensor unplugged, wiring short, seat track issue |
| B00E7 | Medium |
Occupant Classification System Signal Noise | Loose connector, EMI interference, weak sensor signal |
| B00E8 | High |
Occupant Classification System Invalid Data | Corrupted sensor data, BCM communication error |
Severity Key:
-
- Critical: Immediate safety risk (airbag may not deploy)
- High: Safety system impaired (needs prompt attention)
- Medium: Reduced system functionality (should be addressed soon)
- Low: Non-critical fault (may only affect warning lights)
B1000+ Series Body System DTCs
Color Key: Critical | High | Medium | Low
| DTC Code | Severity | Description | Possible Causes |
|---|---|---|---|
| B1000 | Critical |
Airbag Control Module (ACM) Internal Fault | ACM hardware failure, crash data corruption |
| B1001 | High |
Driver Airbag Circuit Low Resistance | Short in wiring, faulty clock spring |
| B1002 | High |
Driver Airbag Circuit High Resistance | Open circuit, disconnected airbag |
| B1003 | High |
Passenger Airbag Circuit Low Resistance | Wiring short, damaged airbag module |
| B1010 | High |
Seat Belt Pretensioner Circuit Malfunction | Faulty pretensioner, wiring issue |
| B1020 | Medium |
Side-Impact Airbag (SIR) Circuit Resistance Low | Short circuit in side airbag wiring |
| B1030 | High |
Airbag System Voltage Low | Weak battery, faulty ACM power supply |
| B1100 | Medium |
Seat Memory Position Sensor Fault | Stuck switch, motor failure |
| B1200 | Low |
Interior Light Control Circuit Malfunction | Blown fuse, faulty BCM |
| B1300 | Medium |
Door Lock Actuator Circuit Failure | Actuator motor failure, wiring issue |
| B1400 | High |
Fuel Door Release Circuit Malfunction | Stuck actuator, wiring short |
| B1500 | Medium |
Horn Control Circuit Failure | Faulty horn relay, clock spring issue |
| B1600 | Critical |
Anti-Theft System (Immobilizer) Malfunction | Key transponder fault, antenna issue |
| B2100 | High |
Tire Pressure Monitor (TPM) System Fault | Failed sensor, receiver module issue |
| B2200 | Medium |
Rain Sensor Circuit Malfunction | Dirty windshield, faulty sensor |
| B2300 | Low |
Ambient Light Sensor Circuit Failure | Sensor unplugged, wiring damage |
Severity Breakdown
-
- Critical (B1000, B1600): Disables safety systems (airbags/immobilizer).
- High (B1001-B1030, B1400): Impacts airbags, seatbelts, or security.
- Medium (B1020, B1300): Comfort/convenience system faults.
- Low (B1200, B2300): Non-safety related (lights/sensors).
Troubleshooting Tips
- Airbag Codes (B1000-B1030):
- Check clock spring and wiring harnesses.
- Never probe airbag circuits with power applied!
- Immobilizer (B1600):
- Reprogram keys or replace antenna ring.
- Seat/Memory (B1100):
- Recalibrate position sensors.
- TPMS (B2100):
- Relearn tire sensors or replace faulty units.
B2000+ Series Body System DTCs
Color Key: Critical | High | Medium | Low | 
Info
| DTC Code | Severity | Description | Possible Causes | UNIQUE FIXES |
|---|---|---|---|---|
| B2000 | High |
Adaptive Headlight System Failure | Stepper motor fault, level sensor issue | |
| B2101 | Medium |
Lane Departure Warning (LDW) Camera Malfunction | Misaligned camera, dirty windshield | |
| B2200 | High |
Blind Spot Detection (BSD) Radar Fault | Sensor misalignment, wiring damage | |
| B2222 | Info |
Head-Up Display (HUD) Communication Error | Loose connector, graphics module fault | |
| B2300 | High |
Automatic Emergency Braking (AEB) System Offline | Dirty radar/camera, module software bug | |
| B2400 | Medium |
Power Tailgate Position Sensor Fault | Stripped gears, sensor misalignment | |
| B2500 | Critical |
Electronic Parking Brake (EPB) Actuator Failure | Motor seizure, control module fault | |
| B2600 | High |
360° Camera System Image Distortion | Water intrusion, lens calibration needed | |
| B2700 | Medium |
Massage Seat Motor Circuit Short | Pinched wires, failed motor | |
| B2800 | High |
Night Vision System IR Camera Fault | Condensation, power supply issue | |
| B2900 | Low |
Ambient Air Quality Sensor Drift | Contaminated sensor, needs recalibration | |
| B3000 | High |
Trailer Hitch Control Module Communication Loss | CAN bus dropout, module failure | |
| B3001 | Critical |
High-Voltage Battery Contactor Stuck Open | Contactor welding, BMS fault | Requires HV system shutdown |
| B3100 | High |
Battery Preconditioning Heater Failure | PTC heater fault, coolant flow issue | Check thermal mgmt. valves |
| B3150 | Medium |
DC Fast Charging Communication Error | CCS Combo port damage, charger mismatch | Update charger firmware |
| B3200 | High |
Autonomous Driving Camera Sync Loss | Timeout between front/side cameras | Recalibrate sensor fusion |
| B3250 | Critical |
LiDAR Obstacle Detection Blind Spot | Dirty sensor, alignment shift | De-ice/reset LiDAR housing |
| B3300 | High |
Dynamic Air Suspension Height Fault | Leaking bag, compressor overload | Disable load-leveling mode |
| B3350 | Medium |
Vehicle-to-Grid (V2G) Handshake Fail | Grid incompatibility, onboard charger fault | ISO 15118 protocol reset |
| B3400 | High |
Regenerative Braking Torque Mismatch | Inverter communication error | Relearn brake blending curve |
| B3500 | Critical |
Motor Controller Overtemperature | Coolant pump failure, rotor sensor fault | Derate power to 50% |
| B3600 | Info |
Cabin UV Sanitization Cycle Aborted | Door opened during cycle | Reset hygiene mode |
| B3700 | High |
Solid-State Battery SoC Calibration Drift | Cell balancing fault | Deep discharge/recharge cycle |
| B3800 | Critical |
Autonomous Emergency Steering Fault | EPS motor overload, map data conflict | Override requires scan tool |
System-Specific Insights
- ADAS Codes (B2101-B2300)
- Calibration Required after windshield replacement (LDW/AEB cameras).
- BSD radar misalignment often occurs after bumper repairs.
- Lighting (B2000)
- Adaptive headlight failures may trigger “Dipped Beam Only” failsafe mode.
- Parking Brake (B2500)
- Emergency release procedure may be needed to move vehicle.
- Night Vision (B2800)
- Common in luxury vehicles – check for firmware updates first.
B3000+ Series Body System DTCs
| B3001 | Critical |
High-Voltage Battery Contactor Stuck Open | Contactor welding, BMS fault | Requires HV system shutdown |
| B3100 | High |
Battery Preconditioning Heater Failure | PTC heater fault, coolant flow issue | Check thermal mgmt. valves |
| B3150 | Medium |
DC Fast Charging Communication Error | CCS Combo port damage, charger mismatch | Update charger firmware |
| B3200 | High |
Autonomous Driving Camera Sync Loss | Timeout between front/side cameras | Recalibrate sensor fusion |
| B3250 | Critical |
LiDAR Obstacle Detection Blind Spot | Dirty sensor, alignment shift | De-ice/reset LiDAR housing |
| B3300 | High |
Dynamic Air Suspension Height Fault | Leaking bag, compressor overload | Disable load-leveling mode |
| B3350 | Medium |
Vehicle-to-Grid (V2G) Handshake Fail | Grid incompatibility, onboard charger fault | ISO 15118 protocol reset |
| B3400 | High |
Regenerative Braking Torque Mismatch | Inverter communication error | Relearn brake blending curve |
| B3500 | Critical |
Motor Controller Overtemperature | Coolant pump failure, rotor sensor fault | Derate power to 50% |
| B3600 | Info |
Cabin UV Sanitization Cycle Aborted | Door opened during cycle | Reset hygiene mode |
| B3700 | High |
Solid-State Battery SoC Calibration Drift | Cell balancing fault | Deep discharge/recharge cycle |
| B3800 | Critical |
Autonomous Emergency Steering Fault | EPS motor overload, map data conflict | Override requires scan tool |
Key Technology Breakdown
-
Battery Systems (B3001-B3150)
- Unique Risk: B3001 may strand vehicle if contactors won’t close.
- Pro Tip: B3100 often triggers in sub-zero temps before cabin preheat.
-
Autonomous Driving (B3200-B3250)
- Requires sensor fusion calibration (costs 300−800 at dealers).
- B3250 common after front-end collisions.
-
Charging/Energy (B3350-B3700)
- B3350 V2G failures increasing with bidirectional charger adoption.
- B3700 affects early solid-state battery vehicles (e.g., 2025+ models).\
Emerging Codes (2024+ Models)
-
- B3900: AI Co-Pilot Personality Module CRC Error (Tesla “Chat Mode” failures)
- B3950: Holographic HUD Laser Diode Degradation (Mercedes MBUX issues)
- B3999: Quantum Encryption Key Sync Failure (Cybersecurity lockout)
Did You Know?
-
- B3400 often appears after brake pad replacements until the system relearns.
- B3600 UV sanitization cycles run automatically in some taxis after ride completion.
(Example: “B3500 motor controller faults typically require 3.5hrs diag + HV training certification.”)
Check Also
Understanding U-Codes: Vehicle Communication Network Diagnostics
