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UPS brought me a package yesterday from Coastal, and since it is currently 66F on January 6th (uhh...ok) I thought I would take the time to install it. Getting at that connector is a little awkward but it probably took me 15 minutes start-to-finish. It's not tough at all if you are used to working with automotive wiring, and I was REALLY impressed at how robust the Prius interior pieces are. Some vehicles are really scary to take apart due to fear of breaking things, but definitely not this one!

Once that was done I figured I would take her for a quick shake-down run to the grocery store. The first good sign was that the engine didn't try to start after I pushed Power and tugged the cruise control stock for about 3 seconds. The next good sign was that I was able to move my dead-silent Prius out of my space and down to the road. So creepy and yet so cool! :D Then it was off down the hill toward the store along the same route that I take to work in the morning. I was very pleased that the battery state of charge did not lose a bar since I started in regen down a steep hill and then used a little of that charge to maintain speed over a shallow rise and then the rest of the way down to the stop sign. Then I made a right and found myself on the open road (35-40mph limits and pretty much level) at which point I wanted to cancel EV and light the ICE.

This is where things got a little dodgy. See, other markets get an EV light on the dash to keep you posted on the car's mode of operation. Not so with US spec models, and this poses a slight problem given Coastal's implementation using the Cruise stalk. I must not have tugged the stalk for the full 2 seconds because I was accelerating (rather briskly) on battery power alone, and suddenly watching the SoC drop like a rock. 6 bars...5 bars...4 bars...at that point I was a little worried. So I pulled the cruise control stalk for a three-count and the ICE started up again. But things still didn't seem quite right.

Even with the ICE lit, the Prius was still drawing heavily from the pack at a steady 35mph cruise. My guess is that this is for a very good reason, particularly to keep the ICE at very low load during the first few moments of warmup. It's not something I have ever seen before because the ICE is usually lit just before rolling down-hill under regen. In any event, the battery got down to three bars (still in the blue "normal" range) and then things started looking normal. I cruised maybe a mile to get the rest of the way to the grocery store parking lot and the battery increased back up to 4 bars by the time I got there. I also glanced down to see the ScanGauge reporting 110mpg for the current trip. :D

Right turn into the parking lot, re-engage EV to creep around to head back home (the warm weather really helped...in colder temps I don't think it would have been done with initial warmup by that point) then disengage EV before making a left turn and accelerating back toward 40. Err...try to disengage EV. Once again the ICE didn't light up when I expected it to. I had to hold the stalk a second time, after which the ICE roared to life and I got an unexpected kick in the pants due to the exaggerated accelerator position that I was using. From that point forward I left it in normal mode and headed back up the hill.

The battery re-charged itself under regen and while drawing from the engine as I drove. It was right back up to its normal 6 bars by the time I parked. The result per ScanGauge was 52.6mpg door-to-door. This trip is normally in the low 40s at best, and I attribute the result both to the EV mode and to the unseasonably warm weather.

Now my job is to learn how to use this little device the right way. It should give me a modest FE boost as long as I train my fingers to cancel EV the first time, every time. All I want is to get down that hill without the ICE lighting, and make sure that the ICE doesn't re-light at the end of a trip when it doesn't need to. The rest of the time I'll just stick to modulating the accelerator and letting the computers do the decision making.

Hi Tim:

___Excellent first hand experience and review.

___Have you heard of others that have the Coastal Tech EV solution experiencing being stuck in EV mode for longer then expected? I know Tony has the EV Button and I am now wondering if his acts similarly? I also thought that once you ran the accelerator to a point where current draw from the pack exceeded a threshold, the ICE would automatically come on and would cancel out the EV button/mode entirely. It sounds like some kind of remnant is still being seen after you have dis-engaged from EV using the stalk or high current to force the ICE to come on?

___Another question I have is have you already exceeded 34 mph with EV engaged and it stayed in EV? With MG2 having the capability of 40 mph ICE-Off, I never did like hearing that Toyoa introduced a 34 mph limit with the EV button. I always had a suspicion that this was a marketing ploy just as Ford always mentions a maximum speed of 25 mph under EV when we know it is good up to 39 - 40 mph before an ICE-On condition has arisen.

___Since this was your first impressions, I cannot wait to hear more as you become more acquainted with its use and capabilities. I really like the stealth install in the stalk vs. pressing the button down under the steering column. Being able to move away from your home and down the slope under Regen before ICE-On must be a godsend vs. her starting up for no other reason then to warm some metal which should come later with a little lower SoC anyway!

___Good Luck and thanks for the report.

___Wayne

More experience will give me a better idea of how it really behaves. I have yet to exceed 34mph since I knew about that supposed limit and used regen to stay just south of that number. But I had the same expectation that a deep throttle position would engage the ICE, which is why I pulled away from the one stop rather briskly and was surprised by the engine non-start. It could be that the true limits of EV current draw are somewhat higher than what the computer allows under normal driving conditions. If so, one probably ought to take it extra easy when EV mode is engaged so as not to over-stress the pack. I'm sure Toyota was very careful about how much current draw they will allow, but just the same it would be unfortunate to test the limits of those NiMH cells over the life of the car and find the edge sooner than expected.

The only thing I can add is that I do know the EV cancel works. I tried starting the car and cancelling ICE start, waiting a while, and then after I held the cruise control stalk again the ICE did light. I'll report back after some time experimenting to see what I can learn.

man I so wish I had an EV button... but classic owners have a thermostat hack that can trick the engine into thinking that its at operating temperature... brick I'm sure your going to have SO MUCH FUN with the EV mode since you will realize just how much more efficient than it really is. Like going across the intersection will never be the same again!


I'm sure your scores will improve with right usage from the battery, envious!

Hi!

I just received the EV kit from CoastalETech a few days back but I'm having a heck of a time installing it. I'm not scared off by the wiring, but it's a matter of getting at the **** plug! :confused: In the instructions it looks like they managed to get the whole plastic frame around the glove box off for at least possible access to the plug, but how? Any assistance would be greatly appreciated. :) I'm looking forward to being able to use it - I've seen SO many occasions where I'm needlessly idling, for one thing (a "glide" where the ICE is actually still on according to my ScanGauge), and of course for those annoying *very* short trips. Anyway, sorry to ramble, but I saw the OP has it installed and (mostly) working without too much trouble and was just looking for tips. :)

_Jerad

Locutus - I think I can help you with that! I took a few photos while I was doing the job. Give me a few minutes to upload them and do a little write-up. I did have to wrangle with it a little but it wasn't too bad. Maybe you will see a difference between your approach and what I did.

Here's what the passenger side dash of my Prius looked like when I had all of the trim off in order to access the computer connectors:

http://www.cleanmpg.com/photos/data/500/EV_Dash_Wide.jpg

Getting to this step is pretty simple. First you remove that small square trim piece just below the A/C vent and above the kick panel. I used a little bit of leverage from a screw driver to get the bottom clips free, then used my fingers to pull it the rest of the way out. The A/C vent portion looks daunting but it's pretty simple, too. I just used my fingers to pull the bottom free and then the top. At that point you have access to the side of the lower glove box. This was the part that had me baffled on my first read through the Coastal instructions:

http://www.cleanmpg.com/photos/data/500/EV_Glove_Damper.jpg

The black rod in the top-center of the picture is the glove box damper, and the grey pin below it is the attachment point on the right-hand side of the glove box. That just slides right off. It makes more sense to see it disassembled than assembled. Once this piece is disconnected you can just drop the glove box down by sqeezing it on both sides to allow the tabs to move past the hard-stops. At that point you are done with the trim and ready to get at those connectors. Here's what it looks like from where the glove box normally sits:

http://www.cleanmpg.com/photos/data/500/EV_Computers_From_Box.jpg

That mass of wiring that is partially obscured by the glove box damping mechanism is what you are after. Here's a better view through the A/C vent hole:

http://www.cleanmpg.com/photos/data/500/EV_Computers_Vent.jpg

As the Coastal instructions say, you are after the bottom connector of the right-most bank. Sadly I didn't take a very good picture of it, but it's sitting behind a bunch of wires in that last photo. There are three ways you can get your hands in there: From the left, where the glove box normally is; from below the A/C vent past that kick panel; and directly through the A/C vent hole. My approach was to get my right hand through the A/C vent hole and my left through the glove box hole. By feel, my right hand found and depressed the clip that locks the connector in place while my left hand gave me a little extra leverage to pry it free. From there it's just as the instructions say: bring that connector out the bottom so that you can see and work with it.

To tell you the truth, putting the connector back after I had attached the wire taps was actually harder than getting it out of its socket. The wiring doesn't have a whole lot of give and the connector winds up at a funny angle. You have to get in there with both hands again in order for it to line up properly. Paitience is extremely important but you will get it.

The only other thing I can say is that you need to be careful when putting the trim back in place, particularly the A/C vent cover. The top clips are easy to line up but you have to bend the panel just the slightest bit to get the lower clips to line up with their receptacles. It's best if you get your head down there so you can see where they are supposed to line up rather than trying to do it by feel. Everything else is just the reverse of taking it all apart.

Oh, and I dropped one of my wire taps behind that kick panel, but it pops out the same way the rest of the trim does. You will have to pull up the front part of the trim that runs along the door sill in order to get it free in the event that you have to get in there. Again, re-installation requires care when lining up the clips.

I hope this helps a little.

Cancel is exactly the same as engage -- hold the stalk for
the same 2 or 3 seconds. The lead into the ECU is simply a
toggle, and Coastal's circuit doesn't drag it to ground in
either case until you hold the cruise switch for the given
timeout. Nothing takes into account whether you're in EV
mode or not.
.
You had the heavy battery draw at first because your EV cancel
enabled the engine to start and enter stage 1 warmup (http://techno-fandom.org/~hobbit/cars/five-stages.txt). For the
first minute or so, the system tries to NOT use the engine at
all but rather run it in fuel-gulping retarded mode to warm up
the cats. It really doesn't want the additional load of the
car at that point but it will give it to you if you really really
want it. [Such as kicking back on when your foot is holding
down the accelerator.]
.
Other ways to cancel EV are: exceed 33 mph, or draw more than 80
amps out of the battery. That's when you get the three beeps.
.
To see/confirm that you *entered* EV mode, switch to the
"consumption" bargraph screen, or even "climate" or "audio" --
anything other than the energy-flow one. When you invoke EV
you'll get a beep and it will switch back to "energy", as a
reminder that you should now pay attention to SoC. There is
no confirmation on user-invoked EV mode exit other than maybe
the engine lights, unless it's an error-condition exit such as
the two alternate methods above.
.
My own switch is just a pushbutton on my panel, so I don't have
to wait for a circuit timeout. This is useful because it's
easier to time my foot-lift and EV-invoke to behave exactly like
normal engine shutdown, but while I'm still in stage 2 or 3.
Downside is that occasionally I'm going around a turn or hitting
bumps when I want to do this, the seatbelt retractor locks up,
and suddenly I can't *reach* the button for a sec.
.
It is fun, though, isn't it? Don't overuse it or your MPG will
suffer; remember that excess conversion in/out leaks energy
but there are times when it's definitely exactly the right thing.
.
_H*

Brick - thank you for putting together this extra info. I'll give it another shot tomorrow morning. I think I had figured out where the connector was supposed to be but I had no idea how to get at it - and in step 5 (I think) of the included instructions it looked like the whole frame around the glove box had been removed (which would certainly make things easier). Thanks again - I'll post tomorrow sometime and let you know how it goes!

I took another trip this evening (just so happens that I rented "An Inconvenient Truth") and all's well with the second go-around. I think my problem was simply not holding the cruise control stalk long enough when I wanted out of EV, because I held it for a little longer this evening and the ICE lit right up when I went under load. Still no idea how it is or isn't impacting my FE but that will take many more than today's dozen or so miles to work on.

Hobbit, thanks for the confirmation of Stage I warmup behavior. I'm starting to wonder if I should disengage EV a little earlier than planned so as to to give the ICE a short time under low load/no load conditions before I start demanding power. That might be better for the long-term health of the drivetrain, and possibly the right thing to do for FE as well.

And yes, EV is loads of fun :D. I'm trying to restrict my use by treating as more of a "forced glide" mode than a powered EV function.

Today I actually needed to run down to the grocery store, so I tried the trip again with a slight modification of my technique. As before, I engaged EV right from the start and got 95% of the way down the hill. But rather than waiting for the last moment to light the ICE, went ahead and got it started when I was at relatively low loads. This did mean maybe 20 seconds of idling, and the Prius still favored electric power for about 1/4 mile of 30mph driving. But this was still a huge improvement because the battery never rose or fell from an indicated 6 bars of charge (whatever % that means...I need CAN view).

I also used EV once I entered the parking lot, for a short while upon exiting the parking lot and part way down the access road, and finally for the last few hundred feet to get back into my parking space. RT fuel economy per the ScanGauge was 50.0mpg in temperatures 20F colder than yesterday's segment along the same route. I think that's pretty good considering the 300ft elevation change over the very short trip.

Just to update - I've got it all installed. Once I managed to get access to the plug everything else went smoothly. So far I've only tested it by powering on after I put everything back together and triggering EV right away. One reassuring beep, an automatic switch to the energy screen, and no automatic ICE start. :D I look forward to putting it to actual use probably Tuesday, when I would next need to drive somewhere. (No need for spurious trips until then, even though I *really* want to!!!) Thanks again brick for the info. I'll post my initial experiences in a few days!

OK, first 2 trips taken with EV installed. Some random observations that have probably been noticed by others but surprised me, as well as some initial questions:

- There's no indication that you've switched to EV mode (other than ICE shutdown) if you're already on the energy screen. This was disconcerting at first (for a few minutes I wondered if I had installed it incorrectly??) but I eventually got used to it. My scangauge helped to confirm EV activation, since usually I was already in a glide and the energy screen showed 99.9/no arrows anyway.

- The auto-disengage at 34MPH is somewhat annoying. On a few occasions I was cresting a hill, started a glide, realized I was still ICE on, forced EV mode to go ICE off going down the other side, then I'd hit 34MPH and hear the 3 beeps, ICE would restart, and at least once the ICE shut down again as I continued to gain speed! I'm not sure why 34MPH is the cutoff. Couldn't it just be the normal 41MPH or is there some other reason I don't know?

- My intended primary use of forcing EV during "glides" where I would otherwise still be ICE-on (not fully warmed up or whatever) seems promising, although there was no noticeable MPG increase for my 2 trips this evening comparing to previous identical trips in similar conditions. Need to get more used to it, I think.

- I haven't explored what "80 amps" of battery draw feels like yet (which would auto-disengage the EV). Is it more or less than normal glide->pulse transition?

- In cases when I've forced EV coming up to a stop, is it better to let it auto-disengage when I pull away, or manual disengage as I'm pulling away (which allows the ICE to kick on about when it normally would), or manual disengage once I've stopped but well before the light would turn (and would this kick on the ICE for no reason)? Need to explore this more.

- This adds a whole new level of awesomeness to city driving. :cool: I needed to fill up today (54.4 MPG for late december/january???) so I'll get a nice whole-tank comparison as I figure out how to use it more effectively.

- The auto-disengage at 34MPH is somewhat annoying. On a few occasions I was cresting a hill, started a glide, realized I was still ICE on, forced EV mode to go ICE off going down the other side, then I'd hit 34MPH and hear the 3 beeps, ICE would restart, and at least once the ICE shut down again as I continued to gain speed! I'm not sure why 34MPH is the cutoff. Couldn't it just be the normal 41MPH or is there some other reason I don't know?



My guess is that this is part of the MG1 protection algorithm. I think what they did was to figure out how quickly a driver could get to 41mph in the worst case scenario, figured out how long it would take the engine to start in that worst case scenario, added a safety margin, and solved backwards for the maximum speed at which they knew they could start the engine and have a 99.98% probability that it would be spinning by the time MG1 was screaming for help at its 10kRPM limit. At least that's what I would have done.


- I haven't explored what "80 amps" of battery draw feels like yet (which would auto-disengage the EV). Is it more or less than normal glide->pulse transition?


As far as I can tell the normal glide/pulse transition is variable depending on any number of factors that I haven't quite figured out. I have read from Prius veterans that this is mainly a function of battery state of charge. Personally I would strive to use the absolute minimum electric current possible. This is mainly for battery life and also because efficiency decreases the higher your current demand is. You would be surprised (or maybe not but I was) at how quick the battery can start losing bars when you get into the throttle before the engine kicks in.


- In cases when I've forced EV coming up to a stop, is it better to let it auto-disengage when I pull away, or manual disengage as I'm pulling away (which allows the ICE to kick on about when it normally would), or manual disengage once I've stopped but well before the light would turn (and would this kick on the ICE for no reason)? Need to explore this more.

My preference would be to get the ICE back in the game as soon as possible under most circumstances. The ECU will let you use quite a bit of energy before forcing you out of EV and that's bound to be bad for efficiency. The one exception I can think of would be when you are pointed down-hill and can pretty much roll up to speed without much in the way of energy input. But in this case you should still be able to disengage EV mode and stealth your way to speed if the engine and cat still have enough heat in them. (It stands to reason that if the engine and cat don't have enough heat in them then you ought to light-up anyway for the sake of emissions.)


- This adds a whole new level of awesomeness to city driving. :cool: I needed to fill up today (54.4 MPG for late december/january???) so I'll get a nice whole-tank comparison as I figure out how to use it more effectively.

Oh, yeah. I'm having all kinds of fun with it. It sounds like you are seeing more of an impact than I am, so I look forward to reading more about your technique after you have had a full tank with it.

One way to avoid the ICE restart while still cold at 34+ is
to pop into neutral on the down. You'll still get the three
beeps as you crest 34 mph but the engine will stay off till
you go back into D. [and it may not even re-light if you've
slowed down in the meantime.]
.
_H*

Hobbit, thanks for that info. I think Wayne asked that exact question a week or two ago but nobody knew what the ICE would do in neutral.

I'm finding that the Phase 1 warmup period goes by pretty darned fast as long as the car is above freezing. This morning I was able to glide down the hill in EV, start the ICE and drive ~1mile at 30-35mph, then shut it back down briefly while cruising down another short grade. I almost want to call it a "FAS Switch" instead of an EV switch. It would even be a genuine use of the acronym for the most part ;) .

Hobbit - cool, I'll have to try that, thanks! (Wait, is there some law about not being in neutral going down hills - even if it doesn't really make sense anymore since going to N doesn't cut out "power brakes" and the like?)

Brick - I was thinking the same thing about calling it the FAS-switch, that's what I've been using it for so far. :) My best use of it as such so far has been on my commute to work (when I need to drive, or conditions are crappy enough to make biking unsafe ;) ): there's a moderate hill that tops about 1/2 mile from work. Before the FAS-switch it would be hit or miss - sometimes I would be ICE-off cresting that hill, and sometimes my "glide" would actually be an idle (with MPG about 5x MPH, according to the scangauge). This was annoying because there was a decent uphill a little later that I would need to burn more gas on, and then even worse as I taxi'd around the parking garage, ICE still on. If I was ICE-off at the top of that hill I could use just a little EV the rest of the way. Now I can "enforce" that. :cool: I have one data point that suggests 3-4 mpg more for this trip just for that and a few other uses. Looking forward to more such comparisons.

(On a related note, I'm off to a heck of a start this tank, probably more due to still-warm conditions, combining trips and other MPG tricks rather than the EV mode, but still - 62.9 MPG over 70 miles :woot: )

A few more observations from the first ~120 miles.

- If you come to a stop in EV mode and cancel it while you are still stopped, the ICE *will* restart unless you are warm enough. From what I've seen so far, "warm enough" means coolant temp >160F, and even then it may still start for a few seconds. What has worked so far for me is to cancel as the light turns green or as I start to pull away. Under normal accel that means the ICE kicks on at 8-10MPH, about when it normally would.

- I've found I need to be careful about throttle position when the cancel takes effect and the ICE restarts, else instead of deadband (red + yellow arrows, nothing to/from the battery, usually IMPG pretty close to MPH), I'll go immediately into high RPM charging (red + yellow + green arrows, IMPG closer to half of MPH), which seems to roughly cancel out any benefit I saw from the previous use of forced ICE-off EV.

- Where I have most benefited so far are short trips where the ICE would never fully warm up anyway (though it tries), for example less than 5 miles of city driving. Looking back at my data there are a few identical trips where temps were ~55F where I was able to match MPG for that trip even with temps now in the 20s. Of course it really depends on the particular trip, but if the ICE isn't going to be able to warm to full stage 4 anyway I think it makes sense to "force glide" as much as possible. :)

Current tank is unfortunately down to 58.6/118 miles - not so much due to temps as to snow (no more cornering at 20+ MPH, have to brake down hills, etc :mad:). I guess I say "unfortunately" tongue-in-cheek since last year at this time I was barely better than 50, but still. ;)

Brick (and others interested in this mod):

Just FYI, I happened across a Google video of someone doing a how-to installation of the Coastal EV switch:

http://video.google.com/videoplay?docid=5377826536782014996

Maybe you're aware of this already.

This is excellent, thank you for posting it! It hits the few :confused: moments I had when installing mine (and others, I would guess), and it's also good to know that I did get it right. :D