DTC P0034-00: Turbocharger/Supercharger Bypass Valve Control Circuit Low: General Description
WARNING: This page is about a different car, the 2021 Kia Soul. However, it is still accessible from the selected car via links, so may be relevant.
Installed on the cooling pan motor top, the Recirculation Valve (RCV) control solenoid valve operates the RCV actuator to control the by-pass passage of the turbocharger compressor.
When the throttle valve is closed during engine running (tip-out), crash noise will be generated from the impeller due to rapid surge in boost pressure.
So, in this case, in order to prevent this phenomenon, ECM maintains the appropriate boost pressure by opening the by-pass passage.