Coastal EV mode up and running

[brick]

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! 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.

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.

[xcel]

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

[brick]

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.

[philmcneal]

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!

[locutus]

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! 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

[brick]

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.

[brick]

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:



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:



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:



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:



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.

[hobbit]

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. 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*

[locutus]

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!

[brick]

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 . I'm trying to restrict my use by treating as more of a "forced glide" mode than a powered EV function.