Code result
P20F5
Reductant Consumption Too High
Moderate severity
What it means
The DEF consumption observed over the dosing window is above the model expectation — typically a leaking injector seat, leaking line fitting, or a pressure-control valve that vents constantly to the tank.
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
Injector seat leaks DEF into exhaust
highOne of the most commonly reported causes for this code — check this first.
Cracked line or fitting
mediumA plausible cause — test and verify before replacing parts.
Related help
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