P0433: Heated Catalyst Efficiency Below Threshold — Bank 2
What to do
Driveable, will fail an emissions test. Ask whether the heater circuit was tested before the converter was condemned.
What this code means
An electrically heated converter on bank 2 is below its efficiency threshold — the counterpart of P0423. Check the heater circuit before the converter: an assembly that never reaches temperature in time fails its monitor with an undamaged substrate.
Likely causes
Start here
- Failed catalyst heater element · specialist
- Failed catalytic converter · specialist
Less common
- Aged or lazy downstream oxygen sensor · easy
- Exhaust leak before the sensor · moderate
Symptoms
Components involved
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
Be the first to write this up
Nothing posted about this yet. Whatever you found is worth writing down — even a dead end saves someone the same afternoon.
What makes one worth reading:
- The car — make, model, year and engine. The same fault behaves differently on each.
- What you measured, not only what you replaced.
- What actually fixed it — or that nothing did, which is worth knowing too.
Sign in or create an account to add what you found about P0433.