EV Button

You have to be going slower than something like 25 MPH to engage. It should do a quick 3-beep warning if it does want to engage. When in EV mode, an EV light will illuminate on the dash.

Curious why you're trying to engage EV mode while driving. There are only a few instances when you should use it.

 

If your T Spirit is like the Gen 3 Prius I have, the EV button is a cruel joke. Anytime I try to press it, the display tells me EV Mode is unavailable. Sometimes it even gives me a reason too.

Some of the time, I suspect, is when the gasoline engine hasn't reached normal operating temperature. Some of the time, again I suspect, is when the traction battery hasn't got a charge beyond a certain amount (enough for normal hybrid operations, but not enough for EV). Other times, the reason given is that I'm going too fast (the 30 MPH speed limit on my residential street is too fast). The EV range is also really pathetic (not quite enough for me to get to the end of my block). Once in a blue moon, I try EV mode and it actually works - for about 100 feet before violating one of the conditions like I want to go down my street at more than just a walking pace.

I'm guessing that you probably need to get the engine warmed up, drive down a hill lightly riding the brakes until you're fully charged, then make sure you are going less than 10 MPH if you want to see what the EV mode does.

I've also got a Gen 4 Prime, which actually does have an EV mode. The Gen 3 Plug-in is also similar based on what I see on some of the YouTube videos. I'm thinking those show me what that EV mode is really supposed to do.

I've concluded (for my case only) that the EV buttons on the standard models are more artifacts from the Plug-in models that somehow made it into the standard models because it was less expensive for Toyota to try to engineer common solutions rather than a totally separate one for each. Like the AM-SAT button on my Gen 3 radio, which doesn't have a satellite receiver.

 

You have to remember a Prius is not an EV, it is a gasoline car with electric assist. The EV range is zero.

The EV button is for suppressing the engine starting so you can drive out of (and back onto) a garage, rearrange the car in a drive or car park, and drive inside (parking garage, parking structure or building, etc).

Your disappointment is really because your expectations are wrong.

Try gliding once the car is fully warmed up (which can take 15 to 20 minutes of driving). Gliding is when no arrows go in any direction on the MFD Energy Monitor screen. In the glide, neither the engine nor the electric motors provide any motive force.

 

From my memory of my recently traded-in Prius, it sounds like your EV mode is functioning as intended, though range ( ) may be a bit reduced by age. Its best use is for parking lot movements, though in my climate zone, even that is locked out when the engine is morning-cold, all but one week a year.

OP's 2008 would be a Gen2, not a Gen3. Some foreign market Gen2s had the EV button, U.S.-market units did not, but some U.S. owners managed to obtain and install the switch. The programming to use it was already in there.

U.S. Gen3 EV mode is unavailable when the engine coolant is below 68F, limited to 10 mph when below some 'warm' temperature, then limited to 25 mph above that temperature. Foreign-market temperature thresholds are different (with different battery warranties too). It is also unavailable when the battery is low.

A "regular" Gen3's EV mode was never anything like what you see in the Gen3 "Plug-In" videos.

Not true, because the Plug-In didn't even exist when your 2011 was built. The Plug-in didn't reach market until 2012, and was done different than what you see on your 2011 non-plug-in.

 

I did the EV hack on my 2007 because it wasn't available in the US market. Found it to be kind of useless and althought it wasn't difficult, I wasn't able to use it for what I wanted, which was to move the car over when clearing snow. When I sold the car I didn't even bother to explain what the little button on the dash was for. I did get a response on the center console from what I remember if EV mode was successful or not.