Powertrain, generic (extended)

P2219 NOx Sensor Heater Control Circuit Low (Bank 2)

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P2219 means the heater control line of the bank 2 NOx sensor is pulled toward ground when it should not be, typically a heater lead chafed against the exhaust or a shorted output stage in the sensor electronics. The control unit then switches the heater off to protect itself. Bank 2 use is not documented by any manufacturer, as known SCR diesels combine both banks. For the bank 1 counterpart P2206, GM's 3.0L Duramax (LZ0) counts 80 failures in 160 samples taken every 25 ms, with relay voltage above 11 V and the dew point passed, and stores a Type B fault lighting the MIL after two trips. Volvo and Mack treat P2206 on their inlet sensor as a sensor failure. P2218 is the open circuit, P2220 the short to power.

Likely causes

Heater lead of the bank 2 sensor chafed through to ground
Shorted heater or output stage inside the sensor
Salt water bridging pins in the connector

Symptoms

  • Malfunction indicator lamp on after two trips
  • Bank 2 NOx sensor stays cold and delivers no value

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€150–1,000
Time0.5–2.5 h

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

Parts involved

nox sensornox sensor heaternox sensor wiring

Related codes

P2206P2218P2220P2223

References: law.cornell.edu, gsi.ext.gm.com, static.nhtsa.gov.