NOx Sensor Circuit Low Input (Bank 2)
What does P2212 mean?
The P2212 code means the vehicle's onboard diagnostic system has detected: NOx Sensor Circuit Low Input (Bank 2). This is a moderate severity code.
Common Symptoms
- Check Engine Light on
- Emissions failure
- Possible limp mode
- SCR warning indicator
- Inaccurate NOx monitoring
Probable Causes (Ranked by Likelihood)
- Open circuit in Bank 2 NOx sensor wiring Very High
- Failed NOx sensor producing low signal on Bank 2 High
- Corroded connector at the Bank 2 NOx sensor Moderate
- Ground fault in the Bank 2 sensor circuit Moderate
- ECM internal circuit fault for Bank 2 Low
Step-by-Step Diagnostic Procedure
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Check Bank 2 NOx sensor signal voltage -- should not be near zero at operating temperature
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Inspect wiring from the Bank 2 sensor to the ECM for opens
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Clean or replace the connector if corrosion is found
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Test the ground circuit for proper continuity
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Replace the Bank 2 NOx sensor if wiring is intact
Frequently Asked Questions
What does low input mean for the Bank 2 NOx sensor?
Low input means the signal from the Bank 2 NOx sensor to the ECM is below the minimum threshold, usually due to an open wire, bad ground, or failed sensor.
Is the Bank 2 NOx sensor in the same location on all vehicles?
No, Bank 2 location varies by vehicle. On V-engines it is the cylinder bank opposite cylinder 1. Consult your service manual for the exact location.
Can I drive with P2212 without immediate repair?
You can drive, but the SCR system cannot properly monitor and control NOx emissions on Bank 2. Some vehicles may enter limp mode, and you will fail emissions testing.