B0420moderate severityBody
Check Engine Lamp Circuit
on 2014 Lincoln MKX 3.7L V6 · AWD
What this code means
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.
Other Body codes on this vehicle
B0001
Driver Frontal Stage 1 Deployment Control
B0001
Driver Frontal Stage 1 Deployment Control
B0002
Driver Frontal Stage 2 Deployment Control
B0002
Driver Frontal Stage 2 Deployment Control
B0003
Passenger Frontal Stage 1 Deployment Control
B0003
Passenger Frontal Stage 1 Deployment Control
B0004
Passenger Frontal Stage 2 Deployment Control
B0004
Passenger Frontal Stage 2 Deployment Control
B0005
Driver Knee Airbag Deployment Circuit
B0005
Driver Knee Airbag Deployment Circuit