What causes a P0415 code?

P0415 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 P0415 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P0415 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

P0415

Secondary Air Injection System Switching Valve B Circuit Malfunction

What it means

Indicates an electrical fault or circuit failure in the secondary air injection system's 'B' switching valve, though rare on heavy-duty diesel platforms compared to light-duty engines.