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TuningBot DTC Database · v4.37.15

P23AC NOx Sensor Circuit Bank 1 Sensor 3

Generic (OBD-II) interpretation in the TuningBot DTC database.

P · PowertrainEmissionsOBD2

What P23AC means

P23AC
NOx Sensor Circuit Bank 1 Sensor 3 Generic · emissions Data confidence 65%

The control module detected a fault associated with the NOx Sensor Circuit Bank 1 Sensor 3 circuit or function; the stored code identifies the affected component rather than a single failure mode.

Symptoms

  • MIL or SCR/AdBlue warning illuminated
  • Possible start-count-down or torque limitation on some applications

Possible causes

  • Reductant quality or level fault
  • Dosing valve or supply module fault
  • NOx sensor fault
  • Frozen or crystallized reductant lines
  • Wiring or connector fault

Recommended checks

  • Read NOx sensor values and dosing system status
  • Check reductant level and quality data
  • Inspect dosing valve, lines and heater operation
  • Check wiring and connectors of the SCR components
  • Check for OEM technical bulletins and software updates

Related and nearby codes

How to read P23AC

P

Powertrain: engine, transmission and driveline systems.

2

Generic SAE-standard code: same meaning on every make.

3AC

Specific fault index within the subsystem.

Frequently asked questions about P23AC

What does P23AC mean?

NOx Sensor Circuit Bank 1 Sensor 3. The control module detected a fault associated with the NOx Sensor Circuit Bank 1 Sensor 3 circuit or function; the stored code identifies the affected component rather than a single failure mode.

Is P23AC generic or manufacturer-specific?

P23AC is a generic OBD-II code: it has the same meaning on every make and model that follows the SAE standard.

Can TuningBot remove P23AC at file level?

If the fault logic lives in the ECU calibration, yes: our DTC Removal file service disables the specific fault entry. Checksum correction is not included: it is a separate, optional service. Not sure whether your case qualifies? Request a free assessment and our engineers will check your ECU file.

Other file services

ECU tuningDyno-tested results by model and engine See the results →

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