Code status
Needs verification
Not yet verified against SAE J2012_202509 / J2012DA. Treat unverified rows as a lookup aid, not repair authority.
- System
- Fuel / Air
- Scope
- iso-sae-controlled-p0
- Standard
- SAE J2012 / ISO 15031-6
- Source
- legacy-import
Diagnostic boundary
A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.
Do not replace the oxygen sensor just because it reports rich; the sensor may be correctly reporting excess fuel or lack of air.
Useful checks before replacing parts
- Review short-term and long-term fuel trims at idle, cruise, and load to see when bank 1 goes rich.
- Check fuel pressure, leaking injectors, purge valve leakage, restricted air intake, biased MAF data, and oxygen or air-fuel sensor plausibility.
- Compare bank 1 and bank 2 data where available to decide whether the fault is bank-specific or engine-wide.
Related OBD-II codes
These nearby fuel / air entries can help compare wording and fault area. They may share the same verification status as the source database.