Powertrain, generic (extended)

P2211 NOx Sensor Heater Sense Circuit High (Bank 1 Sensor 1)

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P2211 flags a heater feedback signal above its permitted range on the upstream NOx sensor of bank 1. An open sense line, a short to supply voltage or an interrupted heater element that the electronics reads as maximum resistance are the usual reasons. GM lists it as NOx Sensor Heater Feedback Circuit High for the 3.0L Duramax (LZ0) in the 2024 Silverado/Sierra. Under CARB rules such circuit faults must be detected regardless of operating conditions. P2210 is the low direction, P2208 the general fault, P2209 the performance check and P2207 the high fault on the control side. The NOx sensor stays unready, SCR control falls back on modelled values, and the MIL lights up.

Likely causes

Interrupted heater element in the NOx sensor
Open sense line or short to voltage
Loose or heat-damaged connector

Symptoms

  • Malfunction indicator lamp on
  • NOx sensor stays not ready

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€250–900
Time0.5–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

nox sensornox sensor heaternox sensor wiring

Related codes

P2208P2209P2210P2212P2207P2224

References: law.cornell.edu, static.nhtsa.gov.