[Normich]

Coastal Technologies sells an add-on to allow the 2004 Prius to operate in electric mode when the driver choses to override the computer. The cost is a moderate $45. A couple of questions: Is this something that is really useful? And for those who have installed this add-on, what is your experience?

Al

 

[Daniel]

I installed Costal's EV switch three of weeks ago. Installation was simple, but difficult to work in the tight space. The instructions fail to mention the need for a very tiny tool to push the pin all the way in. It took me 45 or 50 minutes. Others have completed it in less than the 30 minutes Costal claims.

The EV switch itself is of limited utility, but I like it a lot because it lets me decide whether to let the engine run or not. For moving the car short distances, I can prevent the engine from starting and going into its inefficient warm-up sequence. I can run the last half-mile in electric if the SOC seems too high, so that the next morning's warm-up can be charging the battery. I can glide silently through parking lots and impress the ignorant masses. Stuff like that. It's cool if you're a techno-geek, but it's certainly not necessary.

It does work exactly as advertised. There is no danger of depleting the battery because the ICE will start up if you exceed 34 mph, if you accelerate too hard, if the battery SOC drops to 2 bars, or if you manually shut off EV mode. It will refuse to go into EV mode if the battery SOC is 3 bars or less, if you are moving too fast, if you are accelerating too hard, or if the engine is in its warm-up stage and has not yet reached operating temperature.

 

[BIF]

Daniel, can you tell us whether or not the EV switch might cause problems with warranty work? I wouldn't hesitate to buy one, except for that one tiny little detail.

Thanks!

EDIT: Oh yeah, and I was also wondering if the computer somehow might know or "log" any type of awareness that an EV switch has been plugged in, and/or whether it has been activated.

 

[Brian]

I installed my own EV Button on the Brights Flasher, and there is Danger of ruining the batteries. If you perform many battery S.O.C. Swings, that and damage them. But other than that, it is nice.

 

[Daniel]

The question of the warranty has been discussed. But since I'm not a lawyer, I cannot give you a definitive answer. I'd say that for the installation to affect your warranty, there'd have to be reason to believe that your installation caused the problem for which you are seeking warranty work. I don't believe they could cancel your warranty across the board just because you had made a modification. But that's just my opinion. Of course, if you flub the installation itself, the responsibility is yours. I don't know if an improper installation can fry the computer, but if it does, you pay for the new computer, and I bet that's expensive, and a long wait for the replacement.

The swings in SOC are still controlled by the computer, which will cancel EV mode the instant you drop to 2 bars, so SOC swings are not significantly different than in normal operation. Also note that the Japanese and European versions have the EV button as a factory standard, and that the DIY installation merely uses the pin already in the car, which signals the program already in the computer. You are not overriding anything Toyota has built into this car.

Folks over on Prius Chat have speculated that the car probably does store information that might tell a service tech that the EV switch has been used. I think there's more solid technical knowledge over on the Yahoo groups, if you can deal with the Yahoo user-group format. I cannot.

Finally, let me repeat that the real utility of the EV switch is minimal: it's intended for when you are going to move the car a short distance only, or want to keep the ICE silent for a few blocks of neighborhood driving. It is mainly a techno-geek kind of thing. I like being able to control what the car does, and I'm willing to take what I consider a small risk over the warranty. Your results may vary.

 

[BIF]

Thanks for the thorough explanation, Daniel. I'll probably give it some time before getting one of those.

I might go for the instant engine-light one first.

 

[AgentElrond]

Something I'll definitely consider as well. I've had one or two times where I've been "crawling" into the parking garage at work (posted 5mph), the battery charge looks fine, the A/C is off, but it's running the ICE anyway.

 

[Daniel]

Something I'll definitely consider as well. I've had one or two times where I've been "crawling" into the parking garage at work (posted 5mph), the battery charge looks fine, the A/C is off, but it's running the ICE anyway.

That's the kind of thing that always annoyed me, and I could never figure out. The EV switch solves it. I wish I knew why it did that. Another, analogous situation is when I'm going 20 mph steadily, on a level road, with the SOC at 6 bars, and the ICE all warmed up, and I cannot for the life of me "feather" it into electric. The EV switch solves that one also.

Another thing is that, although stepping too hard on the pedal will kick it out of EV mode, it takes a lot more pedal pressure to kick it out of EV mode than it takes to kick it out of electric mode if you didn't use the EV switch.

 

[ehurtley]

So I just ordered an EV switch, and I have one question:

How fast can you accelerate on EV mode?

I understand that with the EV mode on, it will still engage the ICE if you punch it, but how sprightly is it in EV mode alone? (Will I look like an old grandma if I try to keep it in EV mode, or can I accelerate at a reasonable, if still slower-than-normal, pace?

 

[Daniel]

So I just ordered an EV switch, and I have one question:

How fast can you accelerate on EV mode?

I understand that with the EV mode on, it will still engage the ICE if you punch it, but how sprightly is it in EV mode alone? (Will I look like an old grandma if I try to keep it in EV mode, or can I accelerate at a reasonable, if still slower-than-normal, pace?

I really don't know how to quantify this. Around here most people pull away from a stop pretty gently, and in EV mode I can keep up with them, but I cannot accelerate as fast as I normally do. However, I can stay in EV mode accelerating harder than I would if I was trying to stay in electric mode just by feathering the pedal, without using the EV switch.

Note, however, that with the battery SOC at 4 bars you will travel less than half a mile before the ICE kicks in anyway, so EV mode is not really for hard driving. It's for driving a few blocks when you have a good reason for wanting the ICE not to run, or for driving slowly in a parking lot, etc. If you actually expect to cruise around in golf-cart mode, you'll be disappointed.

"Sprightly" is definitely not the word for the Prius in EV mode. You might not look like a granny, but you'll probably look like a cautious old man. Again, EV mode is really not for driving in traffic, though it does very well if you get up to 33 mph on a level street, and then put it in EV.

If your objective is to prevent the start-up warm-up cycle, you'll have to be pretty gentle with it.

If your objective is to show off, or drain off some excess SOC, then it's no big deal because if the ICE kicks in you can always shut it off again.

I hope this helps. I repeat that the EV is more a techno-geek toy than an especially useful feature. I think it's super-cool. But I'm somewhat of a techno-geek.

 

[ehurtley]

Yes, I am very much a techno-geek. I was wondering mostly because I make quite a few trips to the bank throughout the week, and it's less than 2 miles away of fairly level ground (slight up-hill heading there, slight down coming back. So far, I have been able to keep it in EV mode most of the way driving like a granny.) There are just no sidewalks, or safe shoulders. So I'd like to be able to take that drive on EV-only mode, without having to be so slow.

 

[Daniel]

If your SOC is full (8 bars) there's the off chance you'd make it on the downhill direction. Not on the uphill. And there's no way you'd make the round-trip. Since you'll have to let the ICE run, you might as well let it run from the start and let the car operate the way it's designed.

But since the SOC is never full, your actual range is a lot less. I live 1/2 mile from the grocery store. Sometimes I can make it in EV, and sometimes not. (I tried it just to see if I could.)

At a very rough approximation, I figure 1/4 mile per bar. When it hits 2 bars the ICE starts up. That's 1/2 mile if you start with 4 bars, or 1 mile if you start with 6 bars.

Here's something to keep in mind, though: If you creep silently through parking lots, people are going to think the car is really cool; but if you are always driving like a granny, people are going to think the car has no power.

 

[Bookem_Danno]

EV not engaging

Daniel said, "It will refuse to go into EV mode if the battery SOC is 3 bars or less, if you are moving too fast, if you are accelerating too hard, or if the engine is in its warm-up stage and has not yet reached operating temperature."

A co-worker and I have oberserved instances where EV will not engage when it seems it should. After driving into work for 15-20 min., and with a charge of 7 bars, the EV flasher would not engage for him. I have seen similiar times where warm up should be in effect, but EV is disallowed.

Also, I should hear a triple beep if disallowed. Sometimes, I hear nothing when actuating the flasher, and no EV.

Any thoughts?

 

[finman]

EV mode...

I have had similar experiences with my EV mode on the headlite flasher. Seems like the engine is warm, battery is 6 bars and I'm going 20 MPH in work parking lot. My theory is the battery pack is too hot to use. Ambient temps on these days are above 90 F (94 F and 97 F to be specific). The days when it's cooler (below 90 F), EV mode happens quite easily. My 2 cents worth. I love the headlite mod to force EV mode! Just another 'gadget' but I have a gadget addiction. With the Prius, it's a rush! 8)

 

[finman]

PS

PS If the Energy screen is already showing, there will be no beeps to tell you you are in EV mode. If the Consumption screen is showing, then you will hear a confirmation beep (or 3 beeps if EV mode is not allowed), and it will switch the screen over to the Energy screen.

 

[singpilot]

I bought the EV switch from Coastal, but have not yet installed it. Does it trip the EV logo in the dash, as I have seen a pic of in here?

 

[melgish]

No, sadly it does not.

 

[smtrader]

Anyone around LA (SoCal) area willing/able to give some hands-on guidance in installing this switch?? I want to get it but is scared to death of doing some serious damage to my beautiful car! If someone can walk me through (beyond the directions from Coastal), I would be most grateful. I'd buy you lunch!

 

[Daniel]

Re: EV not engaging

Also, I should hear a triple beep if disallowed. Sometimes, I hear nothing when actuating the flasher, and no EV.

It is possible, as finman said, that high battery temp is another condition that would disallow EV mode. I have no experience of high temperatures. We had a 12-year-record-cold summer this year.

However, it should always give the three beeps when refusing to go into EV, and also when going out of EV for any reason other than that you pulled on the switch again.

If you pull on the switch, and it does not go into EV, and it does not make the three beeps, I would strongly suspect that the switch is not making contact, or you have an intermittent contact somewhere between the switch and the socket.

I have had it refuse to go into EV when I think it should, when my foot is very lightly on the accelerator. I speculate that even though I am not accelerating, the car may be running the ICE harder in order to provide some power to MG1 for charging. In these instances, if I let off the accelerator and engage the switch again, it always goes into EV. I can then press the pedal again, within the limits the EV allows.

 

[Bookem_Danno]

[It is possible, as finman said, that high battery temp is another condition that would disallow EV mode. I have no experience of high temperatures. We had a 12-year-record-cold summer this year.

[/i]

I think Finman has a good hypothesis about the temperature. I would add that I suspect a temperature monitor being located directly on the battery pack. If the battery is being exercised through heavy discharge and regen cycles, the battery will heat up, and possibly prevent EV. One real example I had: I drove home from work (30 min), and went back out within 20 min. on an errand. I had a 1/2 mile slight upgrade, followed by a 1/2 regen. At the light, I tried EV and got the 3-beep. Warm up and charge were good, but I had just exercised the battery on an 85F day.

[However, it should always give the three beeps when refusing to go into EV, and also when going out of EV for any reason other than that you pulled on the switch again.

I believe I have experienced this as well. Not having a confirmation beep nor any EV indicator can lead to some confusion. One trick is to ensure one is in the Consumption display or possible another menu before activating EV. Do you agree?

There is a real need for a smart person to find out how to connect the EV indicator, if possible. Where is it located on the cluster? Far right? Extreme left? Down the middle? (EV could mean Every Vote counts)

[If you pull on the switch, and it does not go into EV, and it does not make the three beeps, I would strongly suspect that the switch is not making contact, or you have an intermittent contact somewhere between the switch and the socket.

I am pretty sure I have good electrical connections.

[I have had it refuse to go into EV when I think it should, when my foot is very lightly on the accelerator. I speculate that even though I am not accelerating, the car may be running the ICE harder in order to provide some power to MG1 for charging. In these instances, if I let off the accelerator and engage the switch again, it always goes into EV. I can then press the pedal again, within the limits the EV allows.

I also confer about engine operation as a prevention.