Code result
P2203
NOx Sensor Circuit High
High severity
What it means
The NOx sensor signal on bank 1 is above the upper limit — short to supply, open ground, or a sensor that failed high. SCR control runs in default mode.
Is it safe to drive?
No — stop driving
This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly.
Most likely causes
Signal wire shorted to supply
highOne of the most commonly reported causes for this code — check this first.
Sensor failed high
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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