My EV, ECO and POWER mode bottons does not activate on my 2012 prius

it is eco/normal/power modes, and ev/hv modes. they are not the same.

how long have you owned it, and when did the issue arise?

 

Is it a Prius V wagon?

 

why do you ask?

 

Because the location of those buttons in the V Wagon (horizontal on the armrest) make them extremely susceptible to collecting spilled drinks, and general "gunk" -- rendering them inoperable. When I bought my V used, the buttons didn't work at all. I had to remove the switch cluster, then disassemble and clean it.
It's a pretty dumb location for a set of switches that rarely get used. Almost as dumb as the location for the heated seat switches -- which are tucked down low out of sight so you can't see them unless you're a Hobbit.

 

All I can offer is to remove the switch cluster and clean it.

 

I have a 2012 Prius v, new to me, still getting used to it, figuring things out, so if something does not make sense to me I assume it's working properly and I don't yet understand why.

So anyway, I've got similar sounding doubts with my buttons. For me, the buttons seem to be just fine. I can press them however I like, and I get instant confirmation up on the dash based on what I pressed. The "problem" is that after doing that, the car seems to switch to whatever mode it wants as soon as it feels a need to do so. So for example, my requests for EV mode are literally (not really) laughed at after a minute or so at most.

Just wondering if this is related to the OP's issue. The dash should instantly respond to any button pushes. I think if it does/does not that would tell you if there is a problem with the buttons themselves. What happens after that is a different issue (or non-issue).

 

It will drop out of EV when EV is inappropriate for any of various good reasons (or if the engine is cool). It will drop out of Power mode when you restart after shut-down. Otherwise, it should not change from whichever mode you select.