Code result
P0601
Internal Control Module Memory Check Sum Error
High severity
What it means
The ECU's internal memory checksum does not match the expected value at startup — the firmware/calibration in flash has become corrupt. Often appears after a failed flash, low battery during programming, or genuine module hardware failure.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Failed flash / interrupted programming
mediumA plausible cause — test and verify before replacing parts.
Module hardware failure
mediumA plausible cause — test and verify before replacing parts.
Module software outdated, reflash may resolve
lowLess common, but worth ruling out after the more likely causes.
Related help
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