The P2223: NOx Sensor Heater Sense Circuit Low Bank 2 refers to a condition where the voltage in the NOx sensor heater sense circuit for bank 2 is lower than expected. This may be caused by a faulty NOx sensor heater, wiring issues, or connector problems, leading to improper heating of the sensor and inaccurate NOx readings.
P2223 – Quick Overview
Code | Information |
---|---|
Meaning | P2223: NOx Sensor Heater Sense Circuit Low Bank 2 |
Is it serious? | Yes, low voltage in the heater sense circuit can lead to improper sensor operation, affecting NOx emissions control and engine performance. |
Possible causes | – Low voltage in NOx sensor heater sense circuit in bank 2 – Faulty NOx sensor heater or wiring issues – Connector problems |
How to diagnose? | – Measure voltage in the NOx sensor heater sense circuit in bank 2 – Test the NOx sensor heater sense for proper operation – Inspect wiring and connectors for faults |
P2223 Meaning
The P2223: NOx Sensor Heater Sense Circuit Low Bank 2 code indicates that the engine control module (ECM) has detected a low voltage signal in the NOx sensor heater sense circuit for bank 2 (the side of the engine that does not contain cylinder 1). The NOx sensor heater is responsible for bringing the sensor up to its operating temperature, ensuring accurate nitrogen oxide (NOx) emissions measurements. Low voltage in this circuit can prevent proper sensor heating, leading to inaccurate NOx readings and emissions control issues.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for any additional related codes that may provide more context for the NOx sensor heater issue. | OBD-II Scanner |
Measure Voltage in NOx Sensor Heater Sense Circuit | Use a multimeter to measure the voltage in the NOx sensor heater sense circuit in bank 2. Verify that the voltage falls within the manufacturer’s specifications. | Multimeter, Vehicle Manual |
Test the NOx Sensor Heater Sense | Use a diagnostic tool or multimeter to test the NOx sensor heater sense for proper operation. Compare the sensor’s output to manufacturer specifications. | Multimeter, Diagnostic Tool |
Inspect Wiring and Connectors | Visually inspect the wiring and connectors associated with the NOx sensor heater sense circuit in bank 2. Look for damaged wires, corrosion, or loose connections that could cause low voltage. | Flashlight, Safety Gloves |
Test Circuit Continuity | Use a multimeter to check for continuity in the NOx sensor heater sense circuit. Low voltage could result from high resistance or a break in the circuit. | Multimeter, Wiring Diagram |
Repair or Replace Faulty Components | If any faulty wiring, connectors, or the NOx sensor heater itself is found, repair or replace them to restore proper voltage and sensor function. | Replacement Parts, Tools |
Clear the Code and Test Drive | After repairs, clear the P2223 code using an OBD-II scanner and take the vehicle for a test drive to ensure the issue is resolved. | OBD-II Scanner |
Recheck for Codes | After the test drive, re-scan the vehicle to confirm that the P2223 code does not return. | OBD-II Scanner |

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