Code result
U0300
Internal Control Module Software Incompatibility
Moderate severity
What it means
A control module has detected that its software version is incompatible with another module on the bus. Most often after a partial update, mismatched coding, or fitting a used module from a different vehicle.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Software/calibration mismatch between modules
highOne of the most commonly reported causes for this code — check this first.
Used module from different vehicle fitted
mediumA plausible cause — test and verify before replacing parts.
Incomplete or interrupted module flash
mediumA plausible cause — test and verify before replacing parts.
Related help
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