I am talking about the manually activated EV mode, not stealth mode that runs up to 46 MPH. I have had the car kick me out of EV mode for excessive speed at 10, 15, or 25 MPH. What determines the top speed? Is it HV battery SOC and/or ICE coolant temperature?
ICE coolant temperature leads to the 10 and 25 mph limits. Below 68F, EV is not available. Above 68F to something much higher (~150??), EV limit is 9 mph. My Scangauge-II has never read right on 68F, but always jumps from 67 to 69. I never ran into a 15 mph limit on my 2010, but did run into an 'excessive acceleration' limit. If you have an actual 15 mph limit, it is new for 2012 and I haven't explored enough to find it.
I spoke with the service manager at my dealership about the 9mph limit. He said he can not change it.
What is the purpose of these limits? My company has several buildings on one large site. Ever now and then I have the need to go from my building to another with heavy test equipment (I usually walk, when not carrying stuff). It is about a 3/4 mile drive. I would like to use EV and avoid using gas at all but I can't crawl at 9MPH. If the EV mode has all these unadvertised restrictions, it defeats having to ability to manually select a mode. Might as well just drive and let the computer decide when to go stealth.
Sorry for my ignorance but what's this "9mph limit"? Mine 2011 always quite the EV mode precisely at 25mph - which is what the manual says...
To keep it simple, your coolent temp needs to be at least 70C (158F). Although on my SGII, it reads 157F. Once it goes down to 155F, i can no longer get it up to 25mph.
This would be another thing to work on if someone could figure out how to read & write to the Prius computer. Mike
Jonny, The Prius is an EV-assist vehicle. If you want true EV performance without the limitations or constraints you're encountering you need to look elsewhere. Electric drive is smooth, quite and powerful. More good news, the market is growing with several choices to meet many different needs.
Mostly speed/power determines the kick out point. You have to have a light touch on the accelerator. It will tolerate up to the red power zone but you need to get it there gradually. Speed, it just shuts off at 25 mph no matter what. I use it a lot at stops and notice I can accelerate faster than the big Diesel pickups so I don't feel like I'm holding up traffic any more than they are when using EV mode.
