What causes a P2000 code?

P2000 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 P2000 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P2000 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

P2000

NOx Adsorber Efficiency Below Threshold Bank 1

What it means

The Engine Control Module (ECM) has detected that the NOx adsorber catalyst (NAC) is not effectively reducing nitrogen oxide emissions as required by environmental standards.