Catalyst System Efficiency Below Threshold (Bank 2)
What it means
Same as P0420 but for bank 2 (the cylinder bank not containing cylinder 1) on V-shaped engines.
Symptoms
Typically just the check-engine light; possible emissions-test failure.
Common causes
Aged catalyst on bank 2, faulty rear oxygen sensor, or an exhaust leak.
Recommended action
Check the downstream O2 sensor and exhaust integrity before condemning the converter.
Related codes
FAQ — P0430
What does code P0430 mean?
Catalyst System Efficiency Below Threshold (Bank 2). Same as P0420 but for bank 2 (the cylinder bank not containing cylinder 1) on V-shaped engines.
What are the symptoms of P0430?
Typically just the check-engine light; possible emissions-test failure.
What causes P0430?
Aged catalyst on bank 2, faulty rear oxygen sensor, or an exhaust leak.
What should I do about P0430?
Check the downstream O2 sensor and exhaust integrity before condemning the converter.
General reference based on the SAE J2012 standard. Exact causes for your vehicle may differ — when in doubt, consult a workshop.
← All OBD-II codes