Code result
P03C3
Cylinder 5 Pressure Too High
High severity
What it means
Cylinder 5 measured peak combustion pressure is above the calibrated maximum — typically pre-ignition, knock, over-fuelling, or runaway combustion.
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
Pre-ignition or knock
highOne of the most commonly reported causes for this code — check this first.
Related help
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