P0432 Code: Main Catalyst Efficiency (Bank 2) — Causes & Fix
P0432 means the main catalytic converter efficiency on bank 2 is below threshold — the converter on the second bank isn't cleaning exhaust well enough.
- Applies to
- All OBD-II vehicles (any make or model)
- Est. repair cost
- $100 – $1,500
- Time to fix
- 30 minutes – 2 hours
What it means
Causes include an aged converter, a lazy O2 sensor, or an exhaust leak on bank 2. P0432 is a generic OBD-II code defined in the SAE J2012 standard, so it applies to virtually any 1996-or-newer OBD-II vehicle regardless of make. Fix the underlying fault, then clear the code with an OBD-II scan tool — it will return if the problem isn't resolved.
Symptoms
- Check engine light on
- Slight economy drop
- Smell; failed emissions
How to fix it
- 1
Verify bank 2 sensors/leaks
1. Rule out a lazy O2 sensor or exhaust leak on bank 2.
- 2
Replace the converter
1. Confirm the fault, then replace the bank 2 converter and clear the code.
Frequently asked questions
Is P0432 like P0430?
Yes — both are bank 2 catalyst-efficiency codes. Check the O2 sensors and for exhaust leaks before replacing the converter.
Last updated July 19, 2026
Guidance only — always consult a qualified professional or the official service manual before carrying out repairs.