Code result
P23C0
NOx Sensor Performance Slow Response High to Low Bank 1 Sensor 3
Moderate severity
What it means
NOx Sensor Performance Slow Response High to Low Bank 1 Sensor 3: the component is electrically intact but its response does not match the command.
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
Sensor element aged
highOne of the most commonly reported causes for this code — check this first.
Sensor element contaminated by oil, soot or coolant
lowLess common, but worth ruling out after the more likely causes.
5V/reference voltage unstable under load
lowLess common, but worth ruling out after the more likely causes.
Related help
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