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 wording
Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.
P0404EGR valve circuit range/performance problemP0404EGR VALVE CIRCUIT RANGE/PERFORMANCE PROBLEMManufacturer communications
2Original wording in English
HONDA
Reported code forms P0404
SERVICE BULLETIN - THE MIL COMES ON WITH DTC P0404 (EGR VALVE CIRCUIT RANGE/PERFORMANCE PROBLEM) RESULTING FROM EXTENDED DRIVING, THE PCM MAY COMMAND EXCESSIVELY HIGH LIFT EGR VALUES THAT MAY DAMAGE AN INTERNAL…
HONDA
Reported code forms P0404
Service bulletin - The MIL comes on with DTC P0404 (EGR valve circuit range/performance problem).
Check vehicle applicability
4A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
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.