How do you fix trouble codes P0654?

Trouble code P0654 indicates a problem with the "Sensor Reference Voltage A." To fix this issue, first, check the vehicle's wiring and connectors for any damage or corrosion that could affect the voltage supply. Next, test the reference voltage using a multimeter to ensure proper voltage levels are being delivered. If the wiring and voltage are fine, the issue may lie in a faulty sensor or the Engine Control Module (ECM), which may need further diagnosis or replacement.