Code result
P0605
Internal Control Module Read Only Memory (ROM) Error
High severity
What it means
ECU self-test detected a ROM/checksum failure on the program memory. The control software cannot be trusted; vehicle typically defaults to limp-home with reduced function.
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
ECU internal ROM fault
highOne of the most commonly reported causes for this code — check this first.
Module software outdated, reflash may resolve
lowLess common, but worth ruling out after the more likely causes.
Supply voltage outside specification
lowLess common, but worth ruling out after the more likely causes.
Related help
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