What Causes A P0121 Code? [Solved]
Hello, iam Melissa Perryman, Have an awesome day! What Causes A P0121 Code? [Solved] When code P0121 occurs, it means that your Engine Control Module (ECM) recognized that your throttle position “A” circuit’s expected output voltage has either gone above or below the sensor’s expected range. When code P0121 is triggered, your ECM will go into failsafe mode.3 Mar 2022 Causes and Fixes P0121 Code Chevy Silverado Quick overview of a...