B0123
Hood Ajar Switch Circuit
1995-1999 BMW 318ti E36 1.9L I4 🇩🇪
Low SeverityBody
Description
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.
Related Codes
Other Body Codes
- B0001Driver Frontal Stage 1 Deployment Control
- B0002Driver Frontal Stage 2 Deployment Control
- B0003Passenger Frontal Stage 1 Deployment Control
- B0004Passenger Frontal Stage 2 Deployment Control
- B0005Driver Knee Airbag Deployment Circuit
- B0006Passenger Knee Airbag Deployment Circuit
- B0010Driver Side Airbag Deployment
- B0011Driver Side Airbag Deployment Circuit Open
- B0012Driver Side Airbag Deployment Circuit Short to Ground
- B0013Driver Side Airbag Deployment Circuit Short to Battery
B0123 on Other Vehicles
Common Questions
What does code B0123 mean on a 1995-1999 BMW 318ti E36?
B0123 stands for "Hood Ajar Switch Circuit". Malfunction in the hood ajar switch circuit used by the theft deterrent system and vehicle status monitoring.
What are the symptoms of B0123 on a BMW 318ti E36?
Common symptoms of B0123 include: Hood ajar warning always on or off, Theft system does not detect hood opening, Interior lights triggered by phantom hood open.
What causes B0123 on a 1995-1999 BMW 318ti E36?
Common causes of B0123 include: Faulty hood switch, Switch out of adjustment, Wiring damage in engine bay, Corroded switch from engine bay moisture.