DTC P0300, DTC P0301, DTC P0302, DTC P0303 Or DTC P0304: Notes

WARNING: This page is about a different car, the 2003 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.

Code Definition

DTC P0300: Random/Multiple Cylinder Misfire Detected.
DTC P0301: Cylinder No. 1 Misfire Detected.
DTC P0302: Cylinder No. 2 Misfire Detected.
DTC P0303: Cylinder No. 3 Misfire Detected.
DTC P0304: Cylinder No. 4 Misfire Detected.

WARNING: Read service precautions before proceeding with service procedure. See SERVICE PRECAUTIONS .

CAUTION: If Engine Control Module (ECM) replacement is instructed in following test, always ensure ECM connectors and ground circuits are okay. If either are defective, repair and repeat testing to confirm ECM malfunction. On models equipped with engine immobilizer, if ECM is replaced, ECM must be programmed with proper ignition key code for engine immobilizer system. For programming procedures, see COMPUTER RELEARN PROCEDURES - TOYOTA article in GENERAL INFORMATION, or appropriate ENGINE IMMOBILIZER SYSTEMS article in ACCESSORIES & EQUIPMENT.