B0102
HVAC Blower Motor Resistor/Transistor Malfunction
Moderateelectrical
Overview
The B0102 code indicates that the body control module has detected a hvac blower motor resistor/transistor malfunction condition. This relates to the vehicle's body electrical systems, which control comfort, convenience, and safety features. When this code is stored, the affected system or component may not operate correctly, potentially impacting safety or comfort features.
Symptoms
- Instrument cluster warning lights erratic
- Turn signals flashing rapidly or not at all
- Airbag warning light illuminated on dashboard
- SRS indicator light stays on or flashes
Common Causes
- Faulty body control module (BCM)
- Low battery voltage or failing alternator
- Corroded or damaged wiring harness connectors
- Failed window/lock/seat motor
Diagnosis Steps
- 1Connect an OBD-II scanner and read all stored body control module trouble codes
- 2Inspect the affected circuit fuse and relay; replace if blown or faulty
- 3Check the wiring harness and connectors for damage, corrosion, or loose pins
- 4Test circuit voltage and ground with a multimeter at the affected component
- 5Verify battery voltage is within specification (12.4V+ engine off)
Estimated Repair Cost
$75 — $800
Cost varies by vehicle, location, and repair shop. Includes parts and labor.
Commonly Affected Vehicles
Toyota CamryNissan AltimaJeep Grand CherokeeVolkswagen Jetta
Related Codes
More Electrical Codes
B0001Driver Frontal Airbag Deployment Loop Circuit Open
CriticalB0002Driver Frontal Airbag Deployment Loop Circuit Short to Ground
CriticalB0003Driver Frontal Airbag Deployment Loop Circuit Short to Battery
CriticalB0004Driver Frontal Airbag Deployment Loop Resistance Too High
CriticalB0005Driver Frontal Airbag Deployment Loop Resistance Too Low
CriticalB0006Passenger Frontal Airbag Deployment Loop Circuit Open
CriticalFrequently Asked Questions
Driving with the airbag warning light on means the SRS system may not deploy in a crash, which significantly increases injury risk. Have the system inspected as soon as possible.