I just tested my Coastal E Tech mod self-installation and it works. Here's tips for others installing it, along with photos. I'm pretty amazed I got something to work whose instructions include the word "wiretap," but, it works.

The installation instructions begin by explaining how to remove the bare minimum required to do this installation - ideally the entire glove compartment assembly would be removed for it but from peeking around that involves taking apart much more of the dash than I'd prefer. As a compromise there is one extra part you can remove. Behind the removed AC grill on the right are 2 screws. Unscrew them - then slide the part they secured to the left. It will take some force because there are 4 plastic tabs still holding it in place but if you just pull hard to the left they'll let loose without breaking. I suppose I'd call this part the Glove Box Restraint.

Image of the right side disassembled
Glove box restraint removed. On the right side you can see the 2 middle grey plugs unplugged and tucked down into a hole. On the top-left of the image is the top grey plug unplugged and tucked away. The orange wire from the kit is plugged into the proper slot and the white clip holding it place is glowing from the flash.

Image of the glove box restraint set aside

This gives you room to put your right hand in through the AC vent and your left hand in from the side.

To create further room unplug all 4 grey plugs down the right side (just like they've done in the diagrams...). You'll never get at the 4th plug (the bottom-right one) otherwise. The top plug ("Plug 1") can be tucked up and to the left. The next 2 can be tucked down and to the left or down and to the right into the small hole at the bottom of the AC vent. I ultimately found the latter to be best with my flashlight pointing up resting on the open glove compartment - shining up meant my fingers didn't block the light much.

The wiretaps are the hardest part of the installation. Begin by identifying one of the wires to tap based on the diagram on the very last page (that numbers the wires in the plug). Then bend the wiretap a little bit to get it started and hold it in your right hand, with the half that has the metal on it on your index finger. Use the wiretap itself to scoop up the necessary wire, then, use your other hand to press the wire into the metal groove. This is the horrible part - it takes a lot of force. You might consider using a flat head screwdriver to push the wire into the groove. Even with this the wires were pretty fussy so to close the taps I had to take my pliers in my right hand and guide them to the taps with my left, and clamp the tap shut with a lot of force on the pliers. If you do use this pliers method check the wiretaps carefully that they're clamping the right stuff and ONLY the right stuff.

The worst is over.

The wire you insert into the plug is surprisingly easy to put in - the only hard part is aiming it, which really is just a matter of good lighting. You can hold the wire itself (keeping your fingers out of the light and away from the connector) when aiming the wire, it will slide in very easily. The side of the connector that sticks out should point towards the top edge of the plug. Once slid in (with the white gate up) it will take force to finish the job - I used needlenose pliers to grab the wire just before the connector - the wire will noticably hit the front of the plug if it's in properly.

The wires that plug into the joints of the wiretaps first slide on, then pop into place - they aren't secured if you haven't heard that nice pop.

Unplugging all 4 plugs earlier means plugging all 4 back in later, so to make it simple to figure out, Plug 3 has the shorter wires and will generally be further from you than Plug 2 (...because of the shorter wires). Plug 1 should be tucked up and to the left so its identity is obvious.

Once you've replugged things I recommend testing your changes - no need to reassemble the glove box/vent assembly to test and, if you screwed up, you'll be happy it's all still hanging open to fix.

The EV mode being engaged is very non-obvious. For one, they state the screen will switch to Energy when it's engaged, but that's already the default screen and the one I leave my car on so that's a non-signal for me. Beyond that there's really no notification that it's engaged - I verified it by turning the car on, waiting for the screen to come up, pulling the Cancel for a count of 4-one-thousand (just to be sure), then waiting 30 seconds (gas normally comes on in 7 seconds). No gas, pulled Cancel for about 2 seconds and the gas kicked in. Pulled it again for about 2 seconds and I heard 3 beeps, the error beep for EV mode not being allowed (because the car was in warm up). Success!

I also had a brief scare starting the car after plugging everything in because most of the dash lights were on... until I realized I'd hit Power without holding the Brake so it was just the standard intermediary power mode. *phew*

 

Wonderful!

So far, no one has found a 'nice' EV mode for the NHW11 that doesn't require: (1) throwing horrible looking codes (aka., disabling the ICE) or (2) driving in reverse (always exciting!)

Bob Wilson

 

First post updated with photos.

How very strange Bob, is it because the signal required to trigger it is complex? Or is the EV mode flatly not present in the computer of the NHW11?

 

The EV switch is available in the NHW20s sold in Japan and Europe. It was fairly easy to reverse engineer the signals and that led to the Coastal Electronics mod. But in the NHW11, there are only a few, undocumented pins and no known definition of a EV mode beyond what the control electronics handles today:

http://hiwaay.net/~bzwilson/prius/pri_ECU.html

One of the interesting 'mind experiments' I've had is to figure out if the MG2 resolver and wheel encoders could be 'hacked' to provide a modified "reverse." You'd put the NHW11 in "reverse" and then enable the hack. Although commanded to go in reverse, MG2 would because of the modified resolver signals, actually provide forward power. In case the brake system decided to 'throw a code', the wheel resolvers might also need to be hacked. Regardless, the ICE would shutoff and as far as the car was concerned, we're driving backwards . . .

Bob Wilson

 

Oh so are you saying even the Japanese and Euro versions of the NHW11 didn't have EV mode? That sounds lke a smart but risky hack there - would you actually shift it into Reverse as part of the EV mode request? That could be unnerving!

I'm still collecting data but so far with the EV Mode available the MFD says I'm averaging 65mpg per round trip, which seems to be better than my usual average. It will be interesting to see how this tank closes out.

I'm debating how best to handle the next tank to get a good comparison in place - afterall, California is about to get MUCH warmer, so I could either use the EV mod for the entire tank, or I could go no EV mod for the next tank and EV mod the one after that.. in either case the tank data is going to be increasingly skewed as the temp rises...

Here's my impression of how the mod is helping and hurting my MPG so far:
Help: I can cut out the engine when it tries to run continually during Glides below 35mph; these aren't common but at least at 40mph if the gas is running constantly you're above 100mpg.

Help: I can cut out the engine when it tries to run continually and I'm coming to a stop, instead of it waiting till I get to 0, idling a few seconds and finally cutting out. This has the added benefit of not forcing me to decide whether I want to coast gradually to a stop (maximizing regen) or brake aggressively (minimizing the time the engine burns gas pointlessly). This has lead me to stop much more gradually leaving me with a more full battery than usual - I've had more assist available when accelerating from a light than I had in the past.

Help: When someone in front of me does something stupid causing me to begin a glide, accelerate suddenly, then attempt to Glide, the Prius cpu assumes I'm going to be tapping the gas a lot and keeps burning gas indefinitely. I can dispute the assumption with the EV mod.

Help: The extra battery power available makes pulling into my complex leave me with 5 or 6 bars even though I do so on all electric. I'm fairly sure this is helping to bring my shorter trips way up - as I said I'm getting 65mpg most trips, and my shortest ones used to do much worse.. more like 48mpg.

Help: The hill I roll down from my complex can now be done entirely on electric - I roll out of the complex itself very slowly in Warmup then cut the engine and let the Prius roll like a rollercoaster down the hill - conservation of momentum. Before I'd get to the bottom of the hill with 27mpg to show for it and 7 bars in my battery. Now I get there with 6 bars and 87mpg. Now that's an improvement!

Hurt: When decelerating into a turn, taking the turn, then accelerating out of it, the Cruise Control's position is all over the place - you really can't hold it for 2 seconds until you straighten out at which point you might be doing 25. That's probably not in mileage's best interest.

Hurt: I sometimes accelerate from a light thinking I've switched modes only to discover I have not. Ironically one aid here is that if I manage to accelerate to 35mph during such an accident the car kicks over for me - this has only happened once when I was forcing a Glide, but nonethe;ess it's a surefire way to find out what mode you're really in.

Hurt: The way EV mode turns off is a bit odd. Occasionally turning off EV mode causes the gas engine to come on hard, when I'm lightly pressing the accelerator. It's almost like the Drive mode just keeps doing its thing in the background, and when EV mode turns off, whatever Drive WOULD have been doing at the time, it tries to kick right into it. I don't think the brief high rev is a big impact but it's certainly odd.

 

Correct, neither the NHW11 nor earlier NHW10 had a manual EV switch. Only the Japanese and European NHW20s had a manual EV switch. The best we can do with the North American NHW11 is learn the control laws and exploit them.

As for my proposed, hack for a manual EV, it would be microprocessor controlled. It would have a simple 'mode' button and the control software would handle shifting and switching the signals as needed. But this hack is in competition with several other hacks that have a little higher priority:

• thermistor hack - this puts the NHW11 ICE in a temperature range so the automated EV modes can work. I've already seen a significant improvement in the cold weather but the data suggests it works year round. This significantly improves the city MPG.
• turbo-alternator - this will reclaim, hopefully, enough energy at high speed that the NHW11 will approach NHW20 performance and improve hill-climbing. It will also help higher speeds in daily commuting.

You need to understand that as much as I appreciate the potential of an EV button, I have two other hacks that appear to work well with my NHW11 and give significant improvements.

This is gratifying and looks exactly like how any good engineer should approach the problem. Edison once stated that 99% of all ideas never result in a product. A reporter ask him, if this is so, how do you come up with so many products? Edison answered 'You have to have lots of ideas.' The key is to test and validate these ideas.

Bob Wilson

 

My first tank with EV mode available is posted:
https://www.greenhybrid.com/compare/...r.php?cid=3783

It's certainly my best tank yet. It beats any tank I've logged, whether read from the MFD or the tank (this one is based on the less generous tank) and it outdoes tanks where I've done 0 highway driving (I would say this tank was roughly 10%). On the MFD my worst trip mileage was a 2mi trip making an urgent run to buy soccer cleats, the short trip distance getting me just 48mpg. It was also my first trip using the mod so I didn't know what I was doing yet.

Because my past logged tanks already reflect a wide variety of temperature ranges and driving scenarios I'm going to stick with using the mod going forward and see how the next several tanks play out.

Here's a log of my trip MFD for this tank since the EV mod being installed part-way through the tank. All trips are round-trips, making them elevation neutral; generally speaking they begin with rolling down a hill from my complex, drive on mostly flat roads, then return up said hill.

49.8mpg 2mi
50.1mpg 5.4mi
65.4mpg (some highway) 22.6mi
63.0mpg (some traffic) 28.1mi
63.7mpg (some traffic) 36.3mi
65.1mpg 19.4mi

 

Another place this Mod helps:
Smooth Glide transition: The conventional way to trigger Glide is to let go of the accelerator momentarily causing MG2 resistance to suck away a little bit of momentum while the ICE hopefully kicks out, then lightly press back down to let everything spin free. Under 35mph the EV Mode lets you kick directly into this mode while keeping your foot steady - you never need to step through the stage of losing momentum to the resistance of MG2. Unfortunately, because of Toyota's peculiar (poor?) choice of disabling EV Mode above 34mph instead of 42mph, this technique cannot be used for most Glides.

Efficient Driving with EV Mod:
This appears to be the best technique with the Mod available - this is based on my keeping my car in a large garage at the top of a hill but it should be easy to infer how other situations would fit.
1) Start car normally, try to time finishing backing out with 7s startup of ICE for warmup.

2) Let warmup idle carry the car out of the garage (neither leaving it to idle nor using battery to further accelerate) - this means moving at only 7mph which is safe in a garage.

3) Listen for the engine to rev up and pull EV mode to shut down the ICE as the descent down the hill begins.

4) Sometime later, probably after momentum gained from the hill subsides, the ICE will be needed for acceleration; use it to Pulse & Glide between 29mph and 34mph, using EV Mode to cut out the ICE smoothly as stated above at 34mph; otherwise attempting to Glide at 40 will get you a continually running engine, especially after rolling off down a long hill to start the day.

5) Repeat this pattern 2 or 3 times then attempt a normal Glide at 34; if the engine cuts itself, the next Glide can be at 40; if not, cut it with EV Mode and continue until the ICE cuts willingly.

I used the above steps to get a whopping 75mpg for a round trip of 30mi! And this is in 50F temps, so the temp wasn't skewing my mpg upwards. Unfortunately this particular round trip ended with hitting serious traffic on the final hill cutting my mpg back down to 65mpg... but the technique is out of the bag. I'll see how my next trip goes using the above.

Obviously all of this requires traffic and stop lights to play along nicely, which very often is not the case. I'm beginning to find that high-traffic hours have an obvious negative impact; but extremely low-traffic hours have a negative impact on streets with frequent lights because some of those lights turn yellow suddenly when a car approaches from the other direction, so you lose the ability to predict lights and Glide appropriately. Very annoying.

 

Excellent report!

One minor typo, you probably meant "MG2", not "MG1" but a quick edit can fix it.

Great job!

Bob Wilson

 

Fixed!

70mpg! 70mpg!

This is my best round-trip tank yet:
70.4mpg 28.1mi 80F

Since I live at the top of a hill my MPG is always higher at my destination than when I get in - so when one of my Soccer teammates got in for a ride, he asked about mileage and I pressed the Energy screen to reveal 85.5mpg - he was like "85 what??" I explained it's a lot lower on the highway, but the shock was enjoyable to watch.

Traffic and red lights permitting I feel confident I can get 75mpg on local roads trips longer than 10mi one-way, by using the above EV mode strategy. Getting close... .