Diagnosis & Repair

Check if any other DTCs are on display. If the Subaru Select Monitor or OBD-II general scan tool indicates DTC P0604, replace ECM. If the Subaru Select Monitor or OBD-II general scan tool do not indicate DTC P0604, it is not necessary to inspect DTC P0604.

Fig 1: Identifying DTC P0604: Internal Control Module Memory Check Sum Error, Circuit & Connector Terminals

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