2002 XC70 ECM-6800 Turbocharger Control Valve

[carboncow]

The neighbors kid's car had it's once-every-6-month-freak-out-limp-home issues that is fixed with simple shutdown and restart. He's got a few issues that include a cam solenoid that are reoccurring and a throttle code when the limp-home happens but what I'm really concerned about these that came back quickly...

ECM-6800 Turbocharger (TC) control valve
ECM-4024 Leak diagnostic unit, pump-signal to low
ECM-4010 Leakage detection module, ventil- signal to low
ECM-4000 Canister purchase (CP) valve -signal to low
ECM-6410 Exhaust camshaft reset valve, signal to low

The last one has been there a few months...while the first 4 are new. Are they related to another and/or the camshaft reset valve?

What is the TCV and where is it's location? I looked around for hoses off but saw and heard nothing.

FYI I did the rubber glove test on the PCV system and it's working damn good at idle and mostly good and 2K RMPs.