What causes a P0414 code?

P0414 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 P0414 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P0414 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

P0414

Secondary Air Injection System Switching Valve A Circuit Shorted

What it means

Indicates a short circuit condition in the switching valve circuit of the secondary air injection system, primarily used for emissions reduction during startup.