B0123low severityBody
Hood Ajar Switch Circuit
on 2021 BMW i3 42 kWh Single Motor RWD · RWD
What this code means
Malfunction in the hood ajar switch circuit used by the theft deterrent system and vehicle status monitoring.
Symptoms
- Hood ajar warning always on or off
- Theft system does not detect hood opening
- Interior lights triggered by phantom hood open
Common causes
- Faulty hood switch
- Switch out of adjustment
- Wiring damage in engine bay
- Corroded switch from engine bay moisture
Diagnostic steps
- Check hood switch alignment
- Test switch continuity
- Inspect wiring
- Clean or adjust switch
- Test circuit voltage at BCM
Repair notes
Adjust or replace hood ajar switch. Protect wiring from engine bay heat and moisture.
Other Body codes on this vehicle
B0001
Driver Frontal Stage 1 Deployment Control
B0002
Driver Frontal Stage 2 Deployment Control
B0003
Passenger Frontal Stage 1 Deployment Control
B0004
Passenger Frontal Stage 2 Deployment Control
B0005
Driver Knee Airbag Deployment Circuit
B0006
Passenger Knee Airbag Deployment Circuit
B0007
Rear Left Side Airbag Deployment Circuit
B0008
Rear Right Side Airbag Deployment Circuit
B0009
Rear Center Airbag Deployment Circuit
B0010
Driver Side Airbag Deployment