DATA LINK CONNECTOR
OBD-II regulations (SAE J-1850) standardize Data Link Connector (DLC) configurations. DLC No. 3 connector is located under left side of instrument panel.
FREEZE-FRAME DATA
The ECM records engine operating condition when a misfire, fuel trim (mixture) malfunction or other malfunction (fuel system, calculated load, coolant temperature, fuel trim (mixture), engine speed, vehicle speed, etc.) exists. If more than one fault is detected, only data from the first malfunction is recorded. Recorded data is useful for determining conditions in which the malfunction occurs.
SUMMARY
If no diagnostic trouble codes are present, driveability symptoms exist or intermittents exist, proceed to TESTS W/O CODES article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent procedures.
DTCS P0300-P0306: RANDOM MISFIRE DETECTED
| DTC | Affected Circuit |
|---|---|
| P0300 | Random Misfire Detected |
| P0301 | Cylinder No. 1 Misfire Detected |
| P0302 | Cylinder No. 2 Misfire Detected |
| P0303 | Cylinder No. 3 Misfire Detected |
| P0304 | Cylinder No. 4 Misfire Detected |
| P0305 | Cylinder No. 5 Misfire Detected |
| P0306 | Cylinder No. 6 Misfire Detected |
DTC IDENTIFICATION
Note. When 2 or more codes for a misfiring cylinder are recorded repeatedly, but DTC P0300 is not recorded, it indicates that misfires were detected and stored into ECM memory at different times.