P2206 code meaning
NOx Sensor Heater Control Circuit Low (Bank 1 Sensor 1)
Powertrain system Generic code P22xx codes Check engine light
What P2206 means
A NOx sensor needs its ceramic element heated to several hundred degrees before it can measure. P2206 means the heater control circuit of the first (upstream) NOx sensor on bank 1 reads low, typically a short to ground or a driver output stuck low. CARB requires diesel OBD to detect heater circuit opens and shorts that conflict with the commanded state. GM's 3.0L Duramax (LZ0) lists it as NOx Sensor Heater Control Circuit Low; Volvo and Mack trucks treat P2206 on the inlet sensor as an internal sensor failure and replace the sensor. P2205 is the general heater circuit fault, P2207 the high side, P2208-P2211 the heater sense circuit. The SCR system loses NOx feedback.
P2206 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.5 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2206
- Malfunction indicator lamp on
- SCR or emissions warning on the display
- Usually no change in driveability
Common causes of P2206
- Most likelyInternal heater or control-unit fault in the NOx sensor
- PossibleHeater wiring chafed to ground near the exhaust
- Less likelyMoisture or corrosion in the sensor connector
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Nox sensorNox sensor heaterNox sensor wiringECM
What each part of P2206 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 2 | Area: fuel and air metering (injector circuit). |
| 06 | The exact fault in that area. |
What to do next
- Note P2206 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2206
What does P2206 mean?
P2206 means "NOx Sensor Heater Control Circuit Low (Bank 1 Sensor 1)". A NOx sensor needs its ceramic element heated to several hundred degrees before it can measure. It is a generic code, so it means the same on every make.
Is it safe to drive with P2206?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P2206 fail an emissions test?
Yes, it can. P2206 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2206 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. This is a job for a workshop.
Will P2206 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.