P0430
Get Serviced SoonFix: Medium — get serviced in 1–2 weeksCatalyst System Efficiency Below Threshold (Bank 2) — Same as P0420 for bank 2.
Dashboard light triggered
Check Engine LightWhat to do
Same as P0420 — verify O2 sensors first, then consider cat replacement if confirmed.
Common causes
- Worn-out catalytic converter (bank 2)
- Faulty downstream O2 sensor (bank 2)
- Exhaust leak before the cat
- Unfixed misfire or rich condition that damaged the cat
Estimated repair cost
$300–$2,500
Exact cost depends on the cause, your vehicle, and labor rates in your area.
What to tell your mechanic
Use this script so you sound informed and get a clear diagnosis before agreeing to repairs:
“Code P0430, catalyst bank 2. Can you test the O2 sensors and confirm the cat is actually failing before we replace it?”
About the Check Engine Light
Code P0430 triggers the Check Engine Light. Indicates an issue with the engine or emissions system. Could range from a loose gas cap to a serious engine misfire.
Read full Check Engine Light guideFrequently asked questions
- What does OBD code P0430 mean?
- Catalyst System Efficiency Below Threshold (Bank 2) — Same as P0420 for bank 2.
- What dashboard light does P0430 trigger?
- P0430 triggers the Check Engine Light.
- How serious is P0430?
- Severity: yellow. Fix priority: Medium — get serviced in 1–2 weeks.
- How much does it cost to fix P0430?
- Repair costs typically range from $300–$2,500. The exact cost depends on the root cause and your vehicle.
Related OBD codes (same dashboard light)
These codes also trigger the Check Engine Light: