What causes a P2443 code?

P2443 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 P2443 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P2443 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

P2443

Secondary Air Injection System Switching Valve Stuck Closed Bank 2

What it means

The Engine Control Module (ECM) has detected that the secondary air injection switching valve for bank 2 is stuck in the closed position, preventing fresh air from entering the exhaust stream.