Code result
P23B1
NOx Sensor Heater Control Circuit Open Bank 1 Sensor 3
Moderate severity
What it means
The heater control circuit for the NOx sensor on bank 1 sensor 3 is open. Without the heater the sensor cannot reach operating temperature; readings stay invalid.
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
Open in heater control wiring
highOne of the most commonly reported causes for this code — check this first.
Pin pushed back out of connector body
lowLess common, but worth ruling out after the more likely causes.
Cracked solder joint inside the module or sensor
lowLess common, but worth ruling out after the more likely causes.
Related help
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