P2443 indicates that the secondary air injection system switching valve on Bank 2 is stuck in the closed position. This valve controls airflow from the air pump to the exhaust to reduce emissions during cold starts. The PCM detected that the valve did not open when commanded.
The valve itself is the most common failure. Internal corrosion, debris, or a broken spring can prevent it from opening when commanded.
An open, short, or high resistance in the valve control circuit or ground can prevent the valve from receiving proper voltage or signal.
If the air pump fails to produce sufficient pressure, the switching valve may not open even if the valve is mechanically sound.
Carbon buildup, debris, or a collapsed hose in the secondary air injection system can restrict airflow and cause the valve to appear stuck closed.
Extremely rare. The PCM may fail to send the correct command signal, but this is only considered after all other components and wiring have been thoroughly tested.
Yes, in most cases the vehicle remains drivable. However, the check engine light will be on, and emissions may be affected. It is advisable to diagnose and repair the issue to avoid potential catalytic converter damage over time.
No, replacing the PCM is almost never the correct fix for P2443. The valve itself, wiring, or air pump are the common causes. Replacing the PCM without proper diagnosis is wasteful and unlikely to solve the problem.
The secondary air injection system primarily operates during cold starts and has minimal impact on fuel economy. However, if the system is malfunctioning, the PCM may adjust fuel trims slightly, potentially causing a small decrease in efficiency.
Not directly. The switching valve is electrically operated and not vacuum-actuated. However, a blocked or leaking air hose in the secondary air system can mimic a stuck-closed condition.