How can you fix 502 code Buick terraza?

To fix a 502 code on a Buick Terraza, start by checking for any loose or damaged wiring and connectors related to the engine control module (ECM) and sensors. Next, inspect the intake air system for any leaks that could affect engine performance. If the issue persists, it may be necessary to replace faulty sensors, like the mass air flow sensor or throttle position sensor, and clear the codes using an OBD-II scanner. Always consult the vehicle's service manual for specific diagnostic procedures and recommendations.