What causes a P1280 code?

P1280 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 P1280 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P1280 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

P1280

AMF CAN sensor flow out of range

What it means

The P1280 code on a PACCAR-powered Peterbilt indicates that the Air Mass Flow (AMF) sensor, which communicates over the CAN bus, is reporting a digital signal that is outside the calibrated operating range.