Error code
OBD2 P0423
OBD2P0423
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.
What it means
Heated Catalyst Efficiency Below Threshold.
Severity
moderateCan be driven, but emissions may not meet standards and could cause further damage if ignored.
Summary
P0423 indicates that the heated catalytic converter on bank 1 is not functioning efficiently, which can affect emissions performance.
Common Causes
- Faulty catalytic converter
- Wiring issues related to the oxygen sensor (HO2S) for bank 1
Fixes
FAQ
What does P0423 mean?
P0423 means the heated catalytic converter on bank 1 is not working efficiently, which can affect emissions performance.
How serious is P0423?
It's moderately serious. While you can still drive with this code, it indicates potential issues with your vehicle's emissions system and could lead to further problems if left unresolved.
Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.
More OBD2 codes
- P0400Exhaust Gas Recirculation Flow
- P0401Exhaust Gas Recirculation Flow Insufficient Detected
- P0402Exhaust Gas Recirculation Flow Excessive Detected
- P0403Exhaust Gas Recirculation Control Circuit
- P0404Exhaust Gas Recirculation Control Circuit Range/Performance
- P0405Exhaust Gas Recirculation Sensor 'A' Circuit Low
- P0406Exhaust Gas Recirculation Sensor 'A' Circuit High
- P0407Exhaust Gas Recirculation Sensor 'B' Circuit Low
- P0408Exhaust Gas Recirculation Sensor 'B' Circuit High
- P0409Exhaust Gas Recirculation Sensor 'A' Circuit
- P0410Secondary Air Injection System
- P0411Secondary Air Injection System Incorrect Flow Detected