When if ever to check PCV and cleaning of battery fan?

With 200k miles:

The PCV valve is probably simplest to just replace, they’re around $10 from dealership. Old one likely fine, but who knows.

Hybrid fan, yeah I’d clean, if only to see where it’s at.

Concur: Toyota should maybe strip out that blinking drivers floor mat check, and add a once-in-a-blue-moon service interval for both PCV valve (replace) and hybrid fan (clean).

 

It’s a matter of opinion. If you don’t carry pets on a regular basis, take a peak at the fan, but the intake grill will usually give you a clue.
My fan has never been dirty.
You could shake the pcv, but I would ignore it

 

Should mention: ONLY use spec’d Toyota PCV valve from dealership; they’re specific design, and cheap anyway. If i was gonna set an interval to replace, same as spark plugs? That’s 120k miles or 12 years in States.

 

I always say a new 12v battery and cleaning the hybrid cooling fan is the 1st step before you start working on a bad hybrid battery. You have to eliminate those concerns first.

As for a bad PCV valve, not since the 1970's have I heard of one of those fail... Even the worst most beat up cars I've worked on that I replace the PCV valve on, there was no indication it was not working properly. In my experience people who think there's a risk of PCV valve failure are delusional. Mechanically it's such a simple device there's very little about it that could fail unless you have so much gunk in your engine that valves have already failed and then only maybe is there a slim chance it could get clogged.