Hood Ajar Switch Circuit
2004-2016 Aston Martin DB9 6.0L V12
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
- B0007Rear Left Side Airbag Deployment Circuit
- B0008Rear Right Side Airbag Deployment Circuit
- B0009Rear Center Airbag Deployment Circuit
- B0010Driver Side Airbag Deployment
B0123 on Other Vehicles
Aston Martin DB11
2016-2024 4.0L V8 Twin Turbo
Aston Martin DB11
2016-2024 5.2L V12 Twin Turbo
Aston Martin DB7
1994-2003 3.2L I6 Supercharged
Aston Martin DBS Superleggera
2019-2024 5.2L V12 Twin Turbo
Aston Martin DBX
2020-2024 4.0L V8 Twin Turbo
Aston Martin Vantage
2005-2024 4.7L V8
Aston Martin Vantage
2018-2024 4.0L V8 Twin Turbo
Common Questions
What does code B0123 mean on a 2004-2016 Aston Martin DB9?
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 Aston Martin DB9?
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 2004-2016 Aston Martin DB9?
Common causes of B0123 include: Faulty hood switch, Switch out of adjustment, Wiring damage in engine bay, Corroded switch from engine bay moisture.