NOx Sensor Heater Control Circuit High Bank 1 Sensor 1
What it means
P2207 means the PCM detected an abnormally high voltage in the heater control circuit for the bank 1 sensor 1 NOx sensor. The NOx sensor needs its heater to reach operating temperature so the emissions system can measure nitrogen-oxide output. It's an electrical fault of the sensor's heater circuit or its wiring — often with no immediate driving symptom, though many diesels will eventually derate power if NOx monitoring stays offline.
Can I keep driving? Drivable at first, but many diesels eventually derate power or limit restarts when NOx monitoring fails — fix it before that happens.
Common symptoms
What you'll notice
- Check-engine light on
- Often no immediate driving symptom
- Possible increased NOx emissions / emissions-test failure
- On some diesels, an eventual reduced-power (derate) warning
Common causes
Most likely first
- High voltage (open or short-to-voltage) in the NOx sensor heater control circuit, bank 1 sensor 1Likely
- Faulty NOx sensor (integrated heater element)Common
- NOx sensor harness open or shortedCommon
- Poor connection or corrosion at the sensor connectorLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and inspect the NOx sensor connector and wiring for damage or corrosion.
- Check the heater control circuit for an open or short-to-voltage against spec.
- Verify power and ground to the sensor/heater are within spec.
- Repair any wiring or connector fault found in the heater circuit.
- If the circuit is good, replace the NOx sensor (the heater is built into it) and re-test.
FAQ
Quick answers
Is it safe to drive with P2207?+
Can I just clear P2207?+
Related codes
Often seen with P2207
Read & clear P2207 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.