B0420
Check Engine Lamp Circuit
1999-2000 BMW 323i E46 2.5L I6 🇨🇦
Moderate SeverityBody
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
- 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
B0420 on Other Vehicles
Common Questions
What does code B0420 mean on a 1999-2000 BMW 323i E46?
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 BMW 323i E46?
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 1999-2000 BMW 323i E46?
Common causes of B0420 include: Burnt out MIL bulb/LED, Cluster circuit board fault, Wiring from PCM to cluster damaged, PCM MIL driver failure.