What it means
The bank 2 NOx sensor reports correctly some of the time but intermittently drops out. Often a marginal connector, a wiring chafe or a sensor that fails when warm.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The heater sense circuit for the NOx sensor at bank 1 sensor 1 reports whether the heater is operating as expected. P2210 sets when the module detects a low signal on that sense circuit, which can indicate a short to ground, excessive resistance, or a heater or connector fault.
Common causes
Most likely first.
- Connector intermittent
- Sensor fails when hot
- Harness routed against vibrating component
Symptoms
- Check engine light or NOx warning on
- AdBlue/DEF level or quality warning
- Possible no-start countdown after ignore period
- Failed emissions inspection (NOx)
How to diagnose it
- Save freeze-frame data and check live heater sense data for bank 1 sensor 1 to confirm the low reading and the conditions when it occurs.
- Inspect the bank 1 sensor 1 connector for corrosion, bent or recessed pins, and moisture that could raise resistance.
- Follow the heater sense wiring from bank 1 sensor 1 and look for chafing, heat damage, or a short to ground.
- Check the sense circuit and heater supply and ground using the vehicle wiring diagram and compare results with the manufacturer's specification.
- If the wiring and connections pass, test the sensor heater and sense output under the manufacturer's procedure.
Common fixes
- Clean or repair corroded or loose bank 1 sensor 1 connector terminals.
- Repair a shorted or damaged heater sense wire.
- Restore a poor heater ground or supply connection.
- Replace the bank 1 sensor 1 NOx sensor if its heater sense output remains low despite sound wiring.
Can I keep driving?
If the vehicle runs normally, a short trip may be possible, but avoid extended driving because emissions control may be impaired and an AdBlue/DEF warning or start countdown may follow. Do not ignore a displayed countdown.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.