Monitor Description
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The ECM continuously monitors its internal memory status. This self-check ensures that the ECM is functioning properly. The ECM memory status is diagnosed by internal mirroring of the main CPU and sub CPU to detect Random Access Memory (RAM) errors. If outputs from these CPUs are different and deviate from the standard, the ECM will illuminate the MIL and store this DTC.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Note |
|---|---|---|---|---|---|
| P0604-44 | Internal Control Module Random Access Memory (RAM) Error Data Memory Failure | ECM RAM error (1 trip detection logic). | ECM | Comes on | SAE Code: P0604 |