What causes a P2055 code?

P2055 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 P2055 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P2055 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

P2055

Reductant Injection Air Pressure Sensor Circuit High

What it means

The Engine Control Module (ECM) detects a high voltage signal from the Selective Catalytic Reduction (SCR) air pressure sensor, indicating the sensor or circuit has failed.