Check Engine Lamp Circuit
2004-2016 Aston Martin DB9 6.0L V12
Description
Malfunction in the check engine/MIL indicator lamp circuit in the instrument cluster.
Symptoms
- Check engine light does not illuminate during bulb check
- Light stays on with no DTC stored
- Light flickering
- Cannot determine if engine codes are present
Common Causes
- Burnt out MIL bulb/LED
- Cluster circuit board fault
- Wiring from PCM to cluster damaged
- PCM MIL driver failure
Diagnostic Steps
- Check bulb during key-on bulb check
- Test MIL drive circuit from PCM
- Inspect cluster wiring
- Scan PCM for codes
- Test cluster LED
Repair Notes
Replace MIL bulb/LED in cluster or repair wiring from PCM to cluster.
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
B0420 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 B0420 mean on a 2004-2016 Aston Martin DB9?
B0420 stands for "Check Engine Lamp Circuit". Malfunction in the check engine/MIL indicator lamp circuit in the instrument cluster.
What are the symptoms of B0420 on a Aston Martin DB9?
Common symptoms of B0420 include: Check engine light does not illuminate during bulb check, Light stays on with no DTC stored, Light flickering, Cannot determine if engine codes are present.
What causes B0420 on a 2004-2016 Aston Martin DB9?
Common causes of B0420 include: Burnt out MIL bulb/LED, Cluster circuit board fault, Wiring from PCM to cluster damaged, PCM MIL driver failure.