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Home >> Lexus >> 2012 >> HS 250h >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P0441-U0293) & Circuit Tests) >> SFI System >> DTC P0604: Random Access Memory (RAM) >> Monitor Description
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Monitor Description

The hybrid vehicle control ECU continuously monitors its internal memory status. This self-check ensures that the hybrid vehicle control ECU is functioning properly. It 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 standards, the hybrid vehicle control ECU will illuminate the MIL and set the DTC immediately.

DTC No. DTC Detection Condition Trouble Area
P0604 Hybrid vehicle control ECU RAM errors Hybrid vehicle control ECU