What causes a P2218 code?

P2218 can be triggered by several issues — see the verified probable causes and step-by-step diagnostics shared by mechanics and owners on OBDIY.

Can I drive with a P2218 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P2218 active.

Follow the step-by-step diagnostic on this page, then read the verified fixes contributed by other Heavy Truck owners — the answer marked "Verified Cause" worked for the original poster.

OBDIY

OBD-II

P2218

NOx Sensor Heater Control Circuit Open Bank 1 Sensor 2

What it means

The Engine Control Module (ECM) has detected an open circuit in the heater control system for the downstream Nitrogen Oxide (NOx) sensor. This prevents the sensor from reaching its operating temperature, causing inaccurate emissions readings.