My Prius needs a battery, Toyota denies warranty due to EV button

Got $4500 worth of parts by trading in (or ditching) a $40 non-US-equipped EV button....it's definitely a good deal. Actually if this EV button is not even appear in the frist place, the $4500 is a Cash-for-Clunker-battery from Toyota anyway....LOL

 

You’ve got a point there. I heard about your $4500 Cash for Clunkers trade in, very nice deal. In this neck of the woods we have a similar ‘Demolition-discount’ (for lack of a better translation) of only € 1000 (around $1430). The amount varies per country all over Europe.
Conditions are the new bought car can be used one but has to be newer than the old one, even if it’s only by a month.
The amount is not that much but I’m not complaining, it gave me a nice extra discount on the Prius.

 

I think you’re right Vertex. I commute three days a week from my small home village to a nearby town, about 20 miles in between. I work in the outskirts of the town but getting home from work in the afternoon I still have to pass three traffic lights and finally a drawbridge to get out.

The bridge keeps opening and closing all day, even during rush hour. Depending on the amount of traffic on the water I have to wait somewhere between 3 and 7 minutes before I can cross. For some reason the Prius keeps running for 1 to 2 minutes on it’s gas engine, even if the battery is almost completely full.
This is where the EV button comes in very handy. The Prius can calculate fuel consumption very accurate but it can’t anticipate. I know that right after the bridge there is a stretch of 12 miles of highway and time enough to recharge the battery. So while waiting at the bridge there is absolutely no need to use gas. I always press the EV button there.

For some reason the gas engine (sometimes) stays on for a while at traffic lights as well. Even when the battery is full or mostly full. I can’t figure out why this happens in some cases and not in others. But I’ve been driving the Prius for only a short while, maybe there’s some logic to it.

 

Perhaps it's more useful on an ornery Gen II, but it's standard on Gen III and I have to say I've not used it since I got the car and can't see using it more than once a year -- if I remember to use it in that special situation.

 

my kids think it's fun when I sneak in on "golfcart" mode when I get home. Sometimes I drive right through the yard to the back door and sneak in.

 

From what I know the Gen I series does not have an EV possibility on the ECU, so it only seems possible on the Gen II series: 2004-2009.
If you expect not to use it much I wouldn't bother going thru the hassle. In my case I use it frequently, several times a day. But I guess it's different for every one.

And driving in 'golfcart mode' is also neighborhood-friendly when you have to leave very early in the morning and don't want to wake up the little ones (including your own) in the street.

I can even leave the village (entirely 30 km/h zone) in stealth mode. After about 1.2 miles I take the on ramp to the freeway and at exactly 50 km/h the system overrides the EV button and the gas engine kicks in.

 

Interestingly enough, this thread ranged from 2007-2009 for the most part, all regarding this EV button. Lo and behold, the EV button is now standard in the 2010 and newer US Prii. Proving it was never EV-related. So, can us 2009 and older guys now safely have an EV button installed?

 

2010 and 2007-2009 are different generations.

 

Yep. (Wow, I'm actually agreeing w/tpfun. ) I wouldn't count the 3rd gen having it as an all clear signal to 2nd gen Prius owners.

 

Yep, but it's the same battery.

Nonetheless, that won't stop Toyota from trying to deny a warranty claim for a bad battery in a car with an aftermarket EV button, as Nate experienced.

 

An EV button in a standard Prius (Gen II or Gen III) is a bad idea. The HV pack is too small to propel a 3000 pound Prius for more than a couple of miles at best. HV battery life depends on keeping its SOC - state of charge within narrow limits. The Toyota Hybrid Synergy Drive system accomplishes this task superbly.

Toyota (originally) made a smart decision to have the HSD take nearly complete control over when the car can be driven in EV mode. The Prius driver can maximize time in EV mode by learning to lightly touch the "gas" pedal so that the Prius stays in EV drive as long as the battery has enough charge. The HSD system "automatically" starts the ICE and begins recharging the HV pack regardless of the lightest application of the gas pedal when it decides the HV SOC is too low. Of course, the ICE shuts off when the gas pedal is completely released but you won't get very far by coasting on a level surface.

I have driven my 2005 Prius for nearly 10K miles the past five months. I usually have the HSD monitor showing on the MFD while I'm driving. I no longer try (or almost never try) to force the HSD into EV mode by reducing my foot pressure on the gas pedal. Now, I just drive the Prius conservatively and let the HSD use HV battery power in the way it's programmed to. I have not noticed any increase or decrease in MPG and now drive the Prius almost like a standard non-hybrid car.

Now I'm sure there are many on Priuschat who will disagree with my comments and can honestly state that they have been able to increase their MPG with various techniques such as P&G, etc without harming HV pack life. My intent is to maximize HV pack longevity and it seems logical the way to do that is to allow the HSD do what it was designed to do. Wouldn't it be nice if the HV battery pack lasted for 15 years and 300K miles on 95% of all Gen II and Gen III Prii?

My six year old Prius now has 143K miles with the original HV pack. My goal is to reach 300K miles with the original HV battery and still achieve 50 MPG for eight months of the year (Winter MPG is and always will be lower). At my current pace of 22K miles per year that's about 7 years from now, near my 60th birthday. So far so good......

 

I don't completely disagree with you jadziasman. There is no doubt that the excessive use of the EV button can add wear and tear on the HV battery.

It is however really useful in certain situations. Like for example if I just want to move my car out of the garage to wash it etc, even if the engine is completely cold I can suppress the ICE coming on. I also often use it when I enter a shopping center car park, it just means you don't have to be so careful on the go pedal to prevent the ICE coming on while cruising for a parking space. I try NOT to use it (or hardly ever use it) in general driving however.

BTW, outside the US the EV button is actually standard equipment in many places. For example my 2005 gen2 has the EV button as standard.

 

P&G, when properly done, doesn't use the HV pack at all. P&G uses momentum to store energy, instead of the less efficient chemical process used in the battery.

Tom

 

No it's not a bad idea, as long as the driver understands how best to use it. Many of us who have documented improvement in MPG with the EV button don't use it to propel the car. We use it to force ICE shutdown during gliding, coasting, or braking when the ICE otherwise would run during warmup.

 

this is a bit worrisome. I've had the mod for a couple years now. And rarely use it, in fact I've almost forgot its there. I found it would only engage half the time, depending on ambient temparture, SOC on the pack. During this time of year, it works quite well, but of course in winter or summer heat its hard to get it to engage unless the battery is GREEN. And of course drains it rather quickly.

Im not to worried about needing a new battery, i just drive the car like any other car. So the pack should be in decent condition still. The dealer should be able to look at the data and see how many times the EV mode was engaged, which for me not very often.

best case if you go in for warranty work on the hybrid system, keep your mouth shut and hope the tech doesn't notice the mod.

 

Don't worry about it. In the unlikely event that you ever need to make a battery warranty claim then just remove the EV button before taking it in.

That's interesting. I also get a lot of "EV denial" here in summer but never in winter (winter here is probably too mild to be of any concern to the battery). I've never had the issue of needing "green" SOC to make EV mode though. I can consistently get EV mode as long as the SOC is 4 or more bars. High temperature seems to be the only issue for me.

BTW. I got a bit of improvement in hot weather performance by cleaning the dust and crap out of the battery cooling fan there near the back seat. This is definitely something that's worth doing from time to time if you carry a dog in the back.

The Vegas area is pretty flat isn't it. If so then I think your battery wont be getting stressed very much.

 

I dont have the button mod version, just the wired in one, where you flip the cruise control inward and it activates. ( part of the reason i forgot its there, no flashy button ) I'm not to worried, I plan to trade in or sell the car in the near future.

The las vegas area is about 2200 feet Elevation, and yes there are flat areas, but also long, grades aswell, going either west or eastbound, also south bound into the Primm area, slight grade, where i get about 42MPG or less maintaining speed. On my way to work its all down hill, can coast easily, getting good F/E. But coming back home up Sahara Ave, is 6 miles of a slight maybe 3% grade,( no idea, just i know it heads towards Red Rock) so F/E suffers some. Its very gradual, and alot of people wouldnt notice it unless they drive a hybrid i suppose. A large V8 for example, you wont notice the gradual grades in the las vegas valley.

just load up google earth, and trace your mouse up and down the valley, of las vegas, you will see the increase in elevation. Downtown being the lowest, while far west/east/north/south having higher ele. North less so