P0423moderate severityPowertrain
Heated Catalyst Efficiency Below Threshold (Bank 1)
on 2017 Maserati Levante 3.0L V6 Twin Turbo · AWD
What this code means
The PCM detected the heated catalytic converter on bank 1 is operating below efficiency thresholds. This reduces the converter's ability to clean exhaust gases.
Symptoms
- Check engine light on
- Failed emissions test
- Sulfur exhaust smell
Common causes
- Failed heated catalyst
- Faulty O2 sensor
- Catalyst heater fault
- Exhaust leak
Diagnostic steps
- Scan and confirm P0423
- Review O2 sensor data
- Check catalyst heater operation
- Inspect exhaust system
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0005
Fuel Shutoff Valve A Control Circuit/Open
P0006
Fuel Shutoff Valve A Control Circuit Low
P0007
Fuel Shutoff Valve A Control Circuit High
P0008
Engine Position System Performance - Bank 1
P0009
Engine Position System Performance - Bank 2
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1