P2218 code meaning
NOx Sensor Heater Control Circuit/Open (Bank 2)
Powertrain system Generic code P22xx codes Check engine light
What P2218 means
A NOx sensor cannot measure until its built-in heater has taken the ceramic cell to several hundred degrees, and the sensor electronics switches that heater itself. P2218 reports a break in the heater control path of the bank 2 sensor, either inside the probe or in the lead to the sensor module. No manufacturer documents the bank 2 version. The bank 1 code P2205 is well described: GM's 6.6L LML sets it when an open heater is reported longer than 10 s with the battery at 11 V or more, the 3.0L LZ0 on an open load at the heater control pin, both Type A with the MIL after one trip. Without heating, the bank 2 sensor never becomes ready. P2219 and P2220 are the shorted cases, P2221 the heater sense side.
P2218 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2218
- Malfunction indicator lamp on after one trip
- Bank 2 NOx sensor never reports ready
Common causes of P2218
- Most likelyHeater element in the bank 2 NOx probe burnt through
- PossibleBroken conductor between probe and sensor module
- Less likelyPushed-back or corroded pin 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 heater
What each part of P2218 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). |
| 18 | The exact fault in that area. |
What to do next
- Note P2218 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 P2218
What does P2218 mean?
P2218 means "NOx Sensor Heater Control Circuit/Open (Bank 2)". A NOx sensor cannot measure until its built-in heater has taken the ceramic cell to several hundred degrees, and the sensor electronics switches that heater itself. It is a generic code, so it means the same on every make.
Is it safe to drive with P2218?
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 P2218 fail an emissions test?
Yes, it can. P2218 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 P2218 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P2218 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.