What does this code mean?
The wording below belongs to the named make and communication. Match the complete code, reporting module, model year and engine before applying it.
A code identifies a detected condition, not a part that must automatically be replaced.
Manufacturer communications
1Original wording in English
INFINITI
Reported code forms P1278
MALFUNCTION INDICATOR LAMP ON WITH DIAGNOSTIC TROUBLE CODE P1278, P1279 A/F SENSOR B1 RICH-LEAN / LEAN-RICH RESPONSE. *TT THIS BULLETIN REPLACES PREVIOUS BULLETIN DATED 05/15/04. *TT
Check vehicle applicability
1A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
| Make | Model | Model year |
|---|---|---|
| Infiniti | QX56 | 2004 |
Before replacing a part
Record codes and freeze-frame data. Check battery condition, related codes and visible wiring or hose damage. Follow the vehicle's diagnostic procedure and test results before replacing parts.
Can I keep driving?
A code alone cannot establish whether driving is safe. A flashing malfunction light, severe shaking, overheating, oil-pressure warning or loss of braking or steering needs prompt attention. Stop in a safe place and seek assistance when control or engine safety is affected. Follow the vehicle handbook.