Code result
P23B4
NOx Sensor Heater Sense Circuit Bank 1 Sensor 3
Moderate severity
What it means
A general circuit fault on the heater sense feedback for the bank 1 sensor 3 NOx sensor - the line over which the ECU verifies that the heater is actually drawing current.
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 sense line
highOne of the most commonly reported causes for this code — check this first.
Related help
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