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REVISED: The original flawed procedure is quoted in post #5

OK, I'm modifying the procedure to make it as reproduceable as possible.

Get in your Prius II.
Depress brake and power on Prius
Don't put it in gear, just wait 7 seconds for the engine to turn on.
Wait 3 seconds, if the engine does not power off, turn off your prius, wait 3 seconds and return to step 2.
If your Prius did shut off, your in S2 (I think).


Now I don't know if this will work if the block temp is below 40°C, but I've seen this behavior with block temps between 50-60°C.

The first couple of times I tried it, the engine immediately (1-2 sec) shut off after it lit. It never hapend on power up #1 or #2. If seen it using the above procedure on power up #3 and in some cases not until power up #4. Even with 3 seconds of ICE each power cycle and 4 power cycles to get there, it may still burn less gas than a normal S1 burn-in. For now, I'm not saying this will save gas, but getting around S1 is always cool.

I was able to do it twice. Can anyone confirm?

Poll of "confirmed" "not confirmed should follow this post on this thread in 2 minutes.

Oh Specs:
2007 Prius II.
Factory EV mod installed.
Canadian EBH installed.
SG II (no xgauge) installed.
CanView not installd.

11011011

Hi Dan:

___Remember the DSG technique? I saw the no-assist w/ the ICE taking on power after the second or third but I was not watching SG-II IG numbers or worrying about an S1 bypass at the time so I could not say if an S1 bypass was the case or not?

___Instead of coming to a complete stop, I would punch her out at lets say 15 - 20 mph with the first initial accel off the pack. After maybe 10 seconds of ICE-Run, I would power her off and back on again shutting down the ICE but taking the free DSG coast down (the ultimate Prius FAS) to a stop. From a stop, place her in P, Power off and back on again. Repeat. I could bring her up to 157 degrees F in the 60 – 80 mpg range from dead cold on almost deserted exit and local town roads leaving my old job far south of Chicago in the morning w/ cooler summer temps.

___The technique I described needs a lot explanation and extreme caution however. You are truly dead stick even though she boots back up. In other words, you are not going anywhere until you have stopped, cycled the Power button in P and started over thus DSG or Dead Stick Glide. I am also not sure how good it was for the Prius either but slowly spinning MGSets at 20 mph or less is not a real concern in my book :rolleyes: I am not recommending this but just pointing out that it may follow along similar lines to what you have seen?

___Good Luck

___Wayne

I tried on my way home from work and well Dan, I think your nuts! I did not vote because I want to give it another try tomorrow on my way to work.

My test was ran from a 8 hour cold engine in ~39 degree temp. Turn on car, moved around the lot in EV until the engine came on. Verified the negative value of IGN and came to a stop. Turned off car, waited about 5 sec and turn it back on. drove around in EV until engine came on and still negative IGN values.

I do know that with a warm engine that you can leave S1 early from the start. I seen it all the time when my EBH was working. I really need to get that thing fixed. :(

I will try this in the morning. I don't think I'll have an opportunity to try it when the EBH wasn't plugged in until Sunday.

OK, I'm modifying the procedure to make it as reproduceable as possible.

Get in your Prius II.
Depress brake and power on Prius
Don't put it in gear, just wait 7 seconds for the engine to turn on.
Wait 3 seconds, if the engine does not power off, turn off your prius, wait 3 seconds and return to step 2.
If your Prius did shut off, your in S2 (I think).


Now I don't know if this will work if the block temp is below 40°C, but I've seen this behavior with block temps between 50-60°C.

The first couple of times I tried it, the engine immediately (1-2 sec) shut off after it lit. It never hapend on power up #1 or #2. If seen it using the above procedure on power up #3 and in some cases not until power up #4. Even with 3 seconds of ICE each power cycle and 4 power cycles to get there, it may still burn less gas than a normal S1 burn-in. For now, I'm not saying this will save gas, but getting around S1 is always cool.

Original Post that I'm now agreeing doesn't work. Please use the above procedure to test.
I may be crazy, but I think I may have found a way to bypass S1. It happened on accident when I was dropping my son off at school.


Dial your SG into IGN
Turn on you Prius and tool around REAL slow till the engine lights
Note the negative value reported for IGN (your in S1)
Come to a COMPLETE stop
Turn the car off
Turn the car on and tool around in EV till the engine lights agian.
Notice the "Normal" IGN numbers and note that the engine takes full loads without MG assit (NOT S1).


I was able to do it twice. Can anyone confirm?

Poll of "confirmed" "not confirmed should follow this post on this thread in 2 minutes.

Oh Specs:
2007 Prius II.
Factory EV mod installed.
Canadian EBH installed.
SG II (no xgauge) installed.
CanView not installd.

11011011

Hi Dan:

___Remember the DSG technique? I saw the no-assist w/ the ICE taking on power after the second or third but I was not watching SG-II IG numbers or worrying about an S1 bypass at the time so I could not say if an S1 bypass was the case or not?

___Instead of coming to a complete stop, I would punch her out at lets say 15 - 20 mph with the first initial accel off the pack. After maybe 10 seconds of ICE-Run, I would power her off and back on again shutting down the ICE but taking the free DSG coast down (the ultimate Prius FAS) to a stop. From a stop, place her in P, Power off and back on again. Repeat. I could bring her up to 157 degrees F in the 60 – 80 mpg range from dead cold on almost deserted exit and local town roads leaving my old job far south of Chicago in the morning w/ cooler summer temps.

___The technique I described needs a lot explanation and extreme caution however. You are truly dead stick even though she boots back up. In other words, you are not going anywhere until you have stopped, cycled the Power button in P and started over thus DSG or Dead Stick Glide. I am also not sure how good it was for the Prius either but slowly spinning MGSets at 20 mph or less is not a real concern in my book :rolleyes: I am not recommending this but just pointing out that it may follow along similar lines to what you have seen?

___Good Luck

___Wayne

OK... I've always felt a little dim because I could never figure out what you were doing with a DSG. Were you doing this with a Classic Prius or Prius II? I had always thought that a Prius II throw you in Park if you ever managed to power off at a speed other than 0 MPH. Did you figure out how to get a Prius II to shut down at speed? If so... How exactly. Also, does it have a Power Button (SKS system).

11011011

Hi Dan:

___I used DSG in both. The Prius-I with the key and the Prius-II with the Power Button. Never ever place it in P while you were coasting down to 0 however. Go from D to N while you powered it down and bring her back up but do not touch anything afterwards. Only go to P when you were actually stopped. I tested the P position from about 0.25 mph just to see (less than a crawling speed as in barely moving) and the parking pawls grabbed almost immediately when going to P while booted up in a DSG.

___Good Luck

___Wayne

OK, I'm modifying the procedure to make it as reproduceable as possible.

Get in your Prius II.
Depress brake and power on Prius
Don't put it in gear, just wait 7 seconds for the engine to turn on.
Wait 3 seconds, if the engine does not power off, turn off your prius, wait 3 seconds and return to step 2.
If your Prius did shut off, your in S2 (I think).
OK reconfirmed the above procedure after 6 power cycles the engine vetoed S1. After the 3 cycle I moved from a 3 second delay between steps to a 0.5 second delay between steps. Faster might be better. Also all the testing brought me from a low 4 bar SoC down into a 3 bar SoC. I went ahead and force-charged up to 5 bars so I can test it with a valid charge on the pack in the morning. SoC may make a difference.

Hi Dan:

___I used DSG in both. The Prius-I with the key and the Prius-II with the Power Button. Never ever place it in P while you were coasting down to 0 however. Go from D to N while you powered it down and bring her back up but do not touch anything afterwards. Only go to P when you were actually stopped. I tested the P position from about 0.25 mph just to see (less than a crawling speed as in barely moving) and the parking pawls grabbed almost immediately when going to P while booted up in a DSG.

___Good Luck

___Wayne

OK... color me astonished. I didn't know you got this working with a Prius II. I accidently hit the power button at about 40 KPH (25 MPH) and nothing happened. No beep no power down, nothing. So from what I'm reading on your procedure you do the following (please correct if I'm off)

Power up your Prius II, put in drive and start driving
Acellerate with S1 up to about 15 MPH then shift to N.
While in N and executing a 15 mph NICE-on coast, hit the power button.
At this point the Prius II does NOT automatically place the car in park, but instead powers down with the car in N and executes a dead stick coast
When your done with your dead stick coast, come to a complete stop (Prius II still in N), depress brake and power back on.
This is now the second boot of the Prius and S1 is vetoed?


Is this right?

11011011

Dan, I don't think Wayne was trying to "veto S1" exactly. He's adapted what you've seen here mentioned as "warm up P&G" with the caveat that you MUST come to a complete stop between pulses because to start back up you have to be in Park. This is more the P&G that is done in a non-hybrid with stickshift where the glide is an actual FAS than the powered up spin-over allowed by pedal manipulation in the Prius.

The idea is that if the engine has to run, use it in the most efficient manner possible. In the process you'll end up get the engine up to (more) normal operating temperatures while avoiding as much inefficient running as possible.

In other words, it isn't so much a veto as a shortening.

Hi Dan:

___Close.
Power up your Prius II with the button and immediately place in D on ready.
Pull away under EV.
When the ICE comes on a few seconds later, you have to let it run while it is doing nothing and you continue to accelerate off the pack to your target speed of 12 to 25 mph.
Shift to N and when you see it on the display (about the same time), push the Power Button.
After she shuts down, push the Power Button again to reboot (Do not touch the Shifter as D doesn’t do anything anyway but it is to stay away from P at all costs.)
Continue coasting down to 0 mph (true Prius FAS) while still booted up and still in N.
When you have completed the Dead Stick Glide and come to a complete stop (Prius II still in N), depress brake.
Place shifter in P.
Hit Power Button to shut down the Prius-II.
Hit Power Button to reboot and immediately place in D on ready and take off.
___Repeat. On the second or third cycle, your next accel will come off the ICE and not the pack as you have probably lost a bar or two from the previous accel up to 25 mph and the ICE is again filling the pack and driving the wheels.

___I have no idea if it removes S1 but I do know that after the second or third DSG cycle, the ICE will power the wheels and fill the pack vs. the insane draw off the pack to accelerate while the engine just sits there doing nothing. That non-sense goes away.

___If there is just one major design flaw wrt the Prius-I and II, it is this crazy warm-up cycle. I hate it, I hate it and I hate it some more ;)

___Again, I am not recommending the DSG technique to anyone as I have only shown 2 people this technique live and do not have a Prius of my own to play with unfortunately :(

___Good Luck

___Wayne

OK reconfirmed the above procedure after 6 power cycles the engine vetoed S1. After the 3 cycle I moved from a 3 second delay between steps to a 0.5 second delay between steps. Faster might be better. Also all the testing brought me from a low 4 bar SoC down into a 3 bar SoC. I went ahead and force-charged up to 5 bars so I can test it with a valid charge on the pack in the morning. SoC may make a difference.

You can always count on Dan for some good ol' Prius fun. :)

I followed Dan's modified procedure this evening with SOC at 59% (six bars), temps at 60F, and the EBH powered on for 3 hours before the test. I let the ICE light for 3-4 seconds before power off, and then powered on again after 1 second.

I too got a near immediate ICE cut off (finally! :)) on power cycle #6. I'll try a few variations tomorrow to see if I can reduce the number of cycles.

UPDATE: I did a second test one hour later. I reduced the ICE light time from 3-4 seconds to 2 seconds. I kept the 1 second delay the same. Again, I got a near immediate ICE cut off on power cycle #6. So now we are down to only 12 seconds of S1? It's still a bit of a hassle, and I do find myself wondering about the negative effects of numerous, repeated cycle on-and-offs (not tonight, but if adopted for daily driving). Dan, you are hurting my tank. ;)

Just to play devil's advocate for a moment. By potentially avoiding S1, are we not sacrificing emissions for mileage? I know that one of S1's primary job is to heat up the cat as quickly as possible. Given all of the hypermiler's ICE off time, maybe a way around S1 is a well deserved reward. ;) Or maybe not.

Since it is fresh on my mind and somewhat related, I offer up another piece of S1 information that may not be known:

Many of us are familiar with Dan's "15 minute shopping" gas savings technique. He parks, does not power off, blanks the MFD, and manually locks the car. This allows the driver to avoid an unnecessary (given high ICE temps) & painful S1 at start up 15 minutes later. I use this quite a bit.

Inevitably, I'll return and forget that I am powered on. So I hit the power button, which powers me off. Doggone it! :( However, I've discovered that a subsequent power on within 1 or 2 seconds still allows me to avoid S1. It's as if I never accidentally shut down in the first place.

I don't know if this has any relevance to the testing here, but I offer it just for your own consumption.

More testing tomorrow. Fun, fun. :)

Hi Dan:

___Close.
Power up your Prius II with the button and immediately place in D on ready.
Pull away under EV.
When the ICE comes on a few seconds later, you have to let it run while it is doing nothing and you continue to accelerate off the pack to your target speed of 12 to 25 mph.
Shift to N and when you see it on the display (about the same time), push the Power Button.
After she shuts down, push the Power Button again to reboot (Do not touch the Shifter as D doesn’t do anything anyway but it is to stay away from P at all costs.)
Continue coasting down to 0 mph (true Prius FAS) while still booted up and still in N.
When you have completed the Dead Stick Glide and come to a complete stop (Prius II still in N), depress brake.
Place shifter in P.
Hit Power Button to shut down the Prius-II.
Hit Power Button to reboot and immediately place in D on ready and take off.
___Repeat. On the second or third cycle, your next accel will come off the ICE and not the pack as you have probably lost a bar or two from the previous accel up to 25 mph and the ICE is again filling the pack and driving the wheels.

___I have no idea if it removes S1 but I do know that after the second or third DSG cycle, the ICE will power the wheels and fill the pack vs. the insane draw off the pack to accelerate while the engine just sits there doing nothing. That non-sense goes away.

___If there is just one major design flaw wrt the Prius-I and II, it is this crazy warm-up cycle. I hate it, I hate it and I hate it some more ;)

___Again, I am not recommending the DSG technique to anyone as I have only shown 2 people this technique live and do not have a Prius of my own to play with unfortunately :(

___Good Luck

___Wayne

I too remember Wayne mentioning the DSG while testing the Prius-II, and filed it under "sounds complicated & risky, but worth revisiting later".

After reading the above, this sounds like a potentially attractive technique for those whose drives immediately begin with a significant downhill followed by a stop. In other words, PARKING GARAGES. :)

That's exactly how I leave work, and most of the trip down is spent in S1 with multiple failed attempts to kill the ICE via the EV switch (before the eventual success). Now that Wayne has laid DSG out exactly here, I believe I'll test it out next week.

I will definitely be staying clear of P at all cost. ;)

Just to play devil's advocate for a moment. By potentially avoiding S1, are we not sacrificing emissions for mileage? I know that one of S1's primary job is to heat up the cat as quickly as possible. Given all of the hypermiler's ICE off time, maybe a way around S1 is a well deserved reward. ;) Or maybe not.

I hate S1 as much as the next Prius hypermiler, but you've got a point here. With a truly cold engine I'll take that hit to get the emissions where they should be. What I hate is going through a full S1 where I have shut down for half an hour or something - too long to leave everything powered up, but everything still otherwise warm enough that a forced warmup cycle shouldn't be needed. I might try something crazy like this for that case, but not when starting completely cold (e.g. overnight).

Yes.. I agree, bypassing S1 could be bad for other reasons. My only motive was to understand why under certain conditions I didn't get an S1 hit. I wanted to study it to better understand the state machine.

Here's how I found it. We moved the school my Son goes to. So now I have to drop him off via a car line. Well it's usually about a 10 minute wait at a dead stop then creap and crawl for another minute or two. So I decided I'd shutdown for those 10 minutes at a dead stop and just deal with S1 later. So now I drive one mile to my kids school. Power off and wait. When the line starts moving I power up, 1 second pulse, shift to N, glide to stop and power off. So by the time I've arrived at the exit, I've gone through probably 10 power cycles and had actually done one "real" S1 not but 20 minutes ago. Well low and behold when I exit my kids school, much to my surprise I start (9th or 10th boot) in S2. If I know I can reliably get out of S1 I'm tempted to power down more often to save pack.

Just another tool in the tool chest. But yes, there is a time and place for it's use. You can't use a hammer to drive in a screw... well you can, but it's not a good idea.

Tried DSG at 15 kph and it just totally ignores me. It was like someone cut the lead to the power button, absolutely zero effect. Didn't try it from a cold start since I went out to do more S1V testing.

Thanks for helping me zero in on this "feature"

11011011

Hi Dan,

I just tested the technique. It did not work for me.

The initial conditions were:

Time of day: 6:30 AM
I did not use the EBH before start.
Ambient temp (Garaged) 52F
Wt at first start 72F
Time since last start 48 hours. I had not driven the car in 2 days
SOC 55.5

I tried the technique 11 times with no luck. It continued to run on every start. On the last one I let it run out all the way. It seemed like there was no shortened time. Although I did not have an actual measurment in seconds (Sorry I forgot my watch).

Final conditions were:

Wt after last start 121F
SOC 60.0

I will test again today after car has driven and warmed up. Wt may be factor.

I think bestmapman's test has the right base conditions to check the theories.
There was not warm engine coolant in the thermos bottle (well, unlikely to be
warm after 2 days).

So, all fun aside, you know Toyota designed S1 the way they did to get the
lowest 'bad' emissions possible. 'Less bad' emissions would be the CO2. If
this 'veto' procedure indeed works, it would clearly be a flaw in Toyota's
design. It's hard to make anything bulletproof when there are crazies out
there that do DSG. (no offense, Wayne... ;) ) You guys all know that Toyota
went to great lengths to not even normally allow a shut down Prius to roll in
neutral, right? But they left in a procedure involving removal of a fuse to allow
technicians (ok, mechanics) to roll the car around a service bay. Safety's
important, so try not to shoot yourselves in your collective feet, ok? :) Thanks.

Ok, now back to the fun.

be careful and cheers,
Bill

Tried DSG at 15 kph and it just totally ignores me. It was like someone cut the lead to the power button, absolutely zero effect. Didn't try it from a cold start since I went out to do more S1V testing.

Thanks for helping me zero in on this "feature"

11011011

Dan, I tried DSG 1 time. I wasn't aware of the fact that it wouldn't restart until I came to a complete stop and it kind of freaked me out so I vowed not to try it again until I got more info on how to do it properly. Anyway, what I found was that you have to hit the "power" button and hold down it for several seconds before the ICE dies. I may have to try this again since I have new knowledge. Perhaps I can get a first-hand demo next Friday morning?;)

Edit: Dan, I think you need another answer for the poll: Yes it works but you're still totally nuts Dan:D

I have not tried a second time yet but I have a theory on what is going on here.

If you need multiple restarts to get this to work then there is something else going on. I think the Prius has a timer that says how long to stay in S1. This timer is about a minute long when temps are cold. When they are warm its less than a minute. Maybe something like 20-30 seconds. So here is my theory on what the restarts are doing.

Startup #1 - S1 Timer starts at 0 seconds, EV mode for 10 seconds, Light engine for 5 seconds, turn off car. S1 timer now sets at 15 seconds.

Startup #2 - S1 Timer starts at 15 seconds, EV mode for required 10 seconds, light engine for 5 more seconds, turn off car. S1 timer now sits at 30 seconds.

Continue this two more times and the timer reaches 60 seconds. On that fourth or fifth restart the car has seen it has been in S1 for about 60 seconds and exits S1. This gives the illusion that you vetoed S1.

Now if this S1 timer starts when your in that first EV mode of 10 seconds could you just turn on the car for say 9 seconds and turn it off before the engine starts. Do this about 6-7 times to get the timer up past 60 seconds. Will the engine exit S1 early then? This would save a lot of fuel if it worked this way.

Or does the timer start when the engine turns on? If this is the case then you would not really save any fuel.

Hi Jay:

___SoC might have some input into this but I think your S1 timer idea has a lot of merit!

___IIRC while driving Cheryl’s Prius-II, I would usually arrive into the work parking lot through some stop signs and a security gate on EV at 4 or 5 bars SoC. Performing a DSG on exit (the only place I could because I would wait until everyone else had left the lot and gone home), I would be at 3 bars at the end of the first or second DSG. On the next one, the ICE would begin providing power and the pack would go back into hibernation as it should. The interesting point is that even during the DSG, the Prius-II was booted up w/ the ICE-Off in N and an S1 timer could have been counting down! The first or second DSG took some time as any vehicle going from 12 – 25 mph all the way to 0 mph will and your timer idea is what allowed S1 to disappear, not the DSG technique itself.

___A bit OT again (sorry Dan :(). To add a little curve to the pitch, there was 1 or 2 times when I entered D while finishing off the DSG at 0 mph and the Prius-II would for some reason think all was normal and allow me to take off under EV without having to go through a Power Down and Power back up cycle. I never did figure that out as it happened so few times and I had the vehicle for such a short period but it probably had to do with a braking event sequence. If you guys can figure that one out, DSG’s may become a little more end-user friendly and useful because now, a DSG is exactly like trying to land a 737 into O’Hare with no engines. “You aint goin nowhere but to a stop and cycled that power button thingie” and it is not a place I would like anybody to be in for obvious safety reasons!

___Either way Jay, nice deduction if I do say so myself! You Prius owners are also fun to read about and reply too :)

___Good Luck

___Wayne

Hi All,

I think the Force is right. And I remember reading the S1 timer is 57 seconds some place. My experience is that when the weather is above freezing and the battery is warm, on the morning start, it uses massive amounts of battery then all of a sudden goes ICE. And this happens at the same spot in the road, 1/4 mile out from home every day. The solution is just to go low accelerator to that point. If you accellerate hard during this period, and start witha 3 bar battery (like I usually do), then you can be down to 1 bar in no time. Which is definately not good for mileage during a S2 warmup.

Ok, I think Dan may be on to something. I confirmed it. Sort of. I started out this morning and as soon as the ICE lit, I powered down. By the time this occurred I was at the road stopped anyway so the timing was perfect. Anyway, when I powered back up and took off, I noticed that the usual heavy draw off the pack wasn't occurring like usual. Here's where the sort of part comes in. After I noticed that I was getting the standard heavy pack draw, it was then that I realized that I hadn't brought up the IGN on the SG2.:o :sleep: I guess I would say that it seems like this does work. The EBH was plugged in. I will try again tomorrow morning and try to remember to set the SG for IGN. When I leave form Church to come home I should be able to try it from a cold start without the EBH.

Just as a note when my EBH was working I exited out of S1 in about 30 seconds. I could manually enter EV at the 30 second mark. This may be why you left S1 early diamondlarry. I'm willing to bet that when you try again without the EBH you will have to wait about a minute before you exit S1.

I just tried my theory. It did not shorten S1. They way I see it the only way to shorten S1 is to have an EBH. I can see where turning off the car before S1 is complete may save fuel if you have to drive a short distance or something. I really would not recommend restarting the car multiple times in a row. I know with regular computers you could blow a cap or something by doing something similar. I’m stopping my on/off experiments for now because after two different tests failing I’m just not convinced this will shorten S1.

Not having much success here either.

This morning's test: EBH fired up, temps in the 60s.

(1) Power up
(2) Let the ICE light for one second
(3) Power down for one second
(4) Power up again, and repeat

Again, on cycle #6, the ICE shut down almost immediately. However, after backing out and accelerating, it became clear I was still in S1. Negative IGN & lots of assist.

This afternoon's test: EBH fired up, temps in the 60s.

(1) Power up
(2) Shut down after 7 seconds before ICE lights
(3) Power down for one second
(4) Power up again, and repeat.

I went through 13 cycles (13 * 7 = ~ 130 seconds, more than enough time to cover S1. On cycle 14, I flipped to EV, backed out, and accelerated. Still in S1 with negative IGN & assist.

I'm game for more testing Dan, if you have any ideas. I don't plan on incorporating multiple power on/off cycles into every day driving, but I imagine she can withstand a few tests from time to time. :)

I'm game for more testing Dan, if you have any ideas. I don't plan on incorporating multiple power on/off cycles into every day driving, but I imagine she can withstand a few tests from time to time. :)I've only seen field observations of this within 1 hour of being in S2. The field observations go something like this.


Get into a totally cold car and do normal S1 transitions.
Once in S2 drive to where your trying to go
Power off the car and do what ever stuff you need to do in less than an hour.
Cycle through the procedure 2 or 3 times and your through S1


What Larry observed is more in line with what I was observing... S1 creep for about 50 feet to stop sign. Cycle power and S1 was shortened by half a block. You may need to apply load for this to work right, since it happens quicker if your doing the S1 creep. I just invented the procedure to see if it was reproducible. A really easy way to do it is to try it after you get where your going with a warm engine. Shuts off on the first cycle if the engine is warm.

This may actually consume less net energy than the "lock-the-keys-in-the-car" trick.

11011011

My second test.

Conditions:

Fully warmed up car. Driven for 45 minutes. Shutdown for 10 minutes
WT 167F
Ambient air temp 51F
SOC 61.0

Went through 3 cycles. On the third cycle the ICE shut off almost immediately. The car drove in S3b. It would glide above 35 MPH but not below 34 MPH.

After conducting the two tests. I think that this is a valid procedure for a warmed up Prius. It does not work on a cold Prius.

A really easy way to do it is to try it after you get where your going with a warm engine. Shuts off on the first cycle if the engine is warm.

This may actually consume less net energy than the "lock-the-keys-in-the-car" trick.

11011011

I may have to give this a try. My wife is generally accepting of my hypermiling antics but she does get a little miffed when we have to hurry so fast when were in the store. More than a few times I've heard, "We would be in such a rush if you'd just shut the car off!":o

Edit: Maybe there needs to be a new response in the poll like, "Yes it works in certain conditions?"

I actually remembered to set the SG2 for IGN this morning. I started out by powering up before I got the seatbelt buckled and the ICE started by the time I was finished. The IGN was reading negative numbers as usual. I immediately powered off then powered back on made a quick pulse and threw it in N and coasted to the end of the drive where I stopped and put it back in D. The ICE started and was reading positive IGN numbers and I didn't have the heavy draw off the pack as usual. When I left Church to come home, I tried the same procedure and I was still in S1 when the ICE restarted and I had the usual heavy current draw when first starting out. My conclusion is the same as what bestmapman came up with: This will work only when the engine is not completely cooled off but works great when the engine is still warm. Thanks for the tip Dan. I think I'm going to start using this more often and see if it helps by not draining the HV battery as much.

Yep... I agree this may be pretty useless on a stone cold engine. I didn't piece it all together till ya'll started tinkering with it. Thanks for all the help guys.

11011011

Dan, think of it this way: You may have helped to significantly reduce the strain on the marriages of people like me who insist on rushing through an all too quick trip into a store because we don't want to lose a bar or two from the pack.:p Look out Dr. Phil, Dr. Dan is on the scene.:D

Another way to use could be when your at a long red light or a train crossing. Since when the engine is real warm it skips S1 on the first boot you could:


Come to the train tracks.
Power down
Wait
Power up
Revel in the fact that your in S2


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Bit off topic, but I managed to do a DSG today. Definately freeky.

It's like when you try to hit the power button on your laptop (or PC or server) and nothing happens. There is a feature that most designs implement called "4-second override". It means if Software won't or can't honor your request to power down a computer, I 4-second hold of the power button will pull power at the hardware level.

This is similar (comically so) with the Prius. You push the power button at speed with the stick in N (don't forget!) and nothing happens. But if you keep it down for 4 seconds your AC I (not AC II) with the car ticking along in N. This is especially wierd since your forbidden to shift into N from D if your in AC I. Normally you have to be in AC II for that to be allowed.

Anyway... I know how to do a DSG now.

As far as S1V. It seems that it works better when you apply load, but there is some secret sauce that I haven't quite figured out yet. Can't consistently hit it when I expect it.

I may dig some more on it, or just file it as one of those crazy Prius Hacks.

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Interesting occurence.

Last night the wife sent me out for Chinese food. I went in to the place, paid and came right out. I left the Prius in ready, powered down the MFD and put a newspaper over the MFD (my usual procedure). Well like an idiot, I got into the car and the first thing I did was hit the power button. The car shut down, I thought about cursing (remebering not to curse) and immediately hit the start button. After the alloted seconds the engine started and almost immediately shut off. When I started I was in S4. Wt was 177.

Has anyone experienced this also.

Here is a thought.

It is possible that S1 is Water Temp. dependant more than anything. Is it possible to hack the Water Temp. sensor and send a signal that would be 190F. This might bypass S1. You could have it on until the real Water Temp reached lets say 170f then switch back to normal.

Just a thought.

My thought is yes, and I think that has been done, though I probably wouldn't endorse it. There is so much that is driven off the thermal readings of those sensors, I'd hate to get it wrong.

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Interesting occurence.

Last night the wife sent me out for Chinese food. I went in to the place, paid and came right out. I left the Prius in ready, powered down the MFD and put a newspaper over the MFD (my usual procedure). Well like an idiot, I got into the car and the first thing I did was hit the power button. The car shut down, I thought about cursing (remebering not to curse) and immediately hit the start button. After the alloted seconds the engine started and almost immediately shut off. When I started I was in S4. Wt was 177.

Has anyone experienced this also.

Yes... it was this kinda stuff that got me tinkering with this procedure. Marc reported earlier that he's seen that happen as well.

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Yes... it was this kinda stuff that got me tinkering with this procedure. Marc reported earlier that he's seen that happen as well.

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Yup, the Prius gives you a little window to undo a screwup of Dan's trick.

http://www.cleanmpg.com/forums/showpost.php?p=81284&postcount=11

S1 hacks will be of even greater interest in an era of a potential PHEV-7 conversion. We'll all have trips which will be just a bit longer than our charge will allow, and the thought of a forced, painful S1 on mile 11 of a 12 mile trip after 10 miles of hypermiled grid driving is not pleasant. My reward for grid driving is 9mpg at the very end? Thanks a lot. ;)

The 12 mile trips will be painful. After 10 miles of grid on the highway, I'll be enduring 30-60 seconds of charge depleting S1, followed by another 30 seconds of ICE-on and battery recharging via the ICE in S2......all at 60mph or so (mitigated maybe with some "pulse & N-ICE"). It won't help that my EBH-warmed ICE will have fallen many tens of degrees after 15-20 minutes of grid driving. Trip mpg will fall like a rock.

I'll probably have to establish "PHEV perimeter zones" around my home & work and ensure I choose destinations that fall within them. :)

Hi Marc:

___A bit OT but S1 in an NHW10 – 20 design does not necessarily mean it will be in the NHW30 or whatever the next model designation will be? Honda Accord and HCH PZEV’s achieve Tier II/Bin2 and they do not have anything even remotely simulating S1. I hope Toyota follows their path and gets rid of this thing altogether.

___Another addition … Coolant temps were probably in the 110 degrees F range in the PHEV-6/7 while in Detroit this past January when I was afforded the opportunity to drive it. Maybe an hour prior to the last driver and charging? I am guessing here however … As soon as I hit the button to place her in Normal hybrid mode, she took off on the ICE without any S1 getting in the way. Let us hope Toyota sees the light. Idling away to light off the CAT makes complete sense for emissions but to idle and not use the power and drain the pack to take off is my own version of a hypemilers horrific nightmare. Let us all hope Toyota Japan sees the light wrt this issue.

___Good Luck

___Wayne

Interesting occurence.

Last night the wife sent me out for Chinese food. I went in to the place, paid and came right out. I left the Prius in ready, powered down the MFD and put a newspaper over the MFD (my usual procedure). Well like an idiot, I got into the car and the first thing I did was hit the power button. The car shut down, I thought about cursing (remebering not to curse) and immediately hit the start button. After the alloted seconds the engine started and almost immediately shut off. When I started I was in S4. Wt was 177.

Has anyone experienced this also.

Similar, but if I'm running a 30-45 minute errand, I power up and WT is still above 159, then S1 will only be 20-30 seconds long and when the ICE kills I'm in S4 not S2.

Hi Marc:

___A bit OT but S1 in an NHW10 – 20 design does not necessarily mean it will be in the NHW30 or whatever the next model designation will be? Honda Accord and HCH PZEV’s achieve Tier II/Bin2 and they do not have anything even remotely simulating S1. I hope Toyota follows their path and gets rid of this thing altogether.



Here's hoping. :cool: Given the emissions benefits of the grid charge, you'd think that replacing S1 & S2 with one long S2 to 157F would be acceptable. Just get rid of that heavy ICE use & assist. :o

Geez, a retrofit second NiMH pack & plug, 60mph glide, AND ELIMINATION OF S1? Somebody stop it all. The inevitable disappointments will be too much to bear. ;)

The rest of the Prius crew already figured this out (if they bothered), but it took me until lunch today. With a PHEV-7 on a long highway trip (30-40 miles or greater) you wouldn't want to deal with S1-S3b/S4 transition on the highway. You'd run through your S1-S3b/S4 transition early, and postpone the 7-10 miles of "surge & glide" until well into your trip, say, at mile 10 with coolant temps at 184F. 10 miles of EV/ICE-off later, you still might be above 157F and can pick up where you left off with a highway P&G between 53-60mph.

The future is bright indeed. :D

Instead of thinking of it in terms of the amount of time, it sounds like to me this is what you are trying to do:

power up, let ice run until computer has enough time to check cat and water temp, turn off because it is in s1 and once that starts it has to finish.

restart, computer remembers cat/water temp is good (or checks it quickly) so it doesn't initiate s1.

Anyway, what I'm getting at is you probably need to know the cat temp to be able to perfect this trick.

The 12 mile trips will be painful. After 10 miles of grid on the highway, I'll be enduring 30-60 seconds of charge depleting S1, followed by another 30 seconds of ICE-on and battery recharging via the ICE in S2......all at 60mph or so (mitigated maybe with some "pulse & N-ICE"). It won't help that my EBH-warmed ICE will have fallen many tens of degrees after 15-20 minutes of grid driving. Trip mpg will fall like a rock.Well while I was gathering data what I noticed was that if you were under enough (spelled "a lot") load, the engine wasn't so wimpy in it's power distribution. Basically I'd been messing with this stuff and depleted my pack. I realized the pack was low so after my movie I went back out with the intent of just force charging for a bar so my morning commute wasn't shot. Well to my surprise, if you power it on, then floor it, looks like it gives you full ICE load.

Similarly I think the the following would work:

Start on top of a hill
Shift to N before ICE lights.
NICE-off glide to 40 mph
Shift into drive and accelerate up to 50 mph.


I suspect that step 4 wouldn't give you the wimpy S1 limp.

Bit off topic, but I managed to do a DSG today. Definitely freaky...
Anyway... I know how to do a DSG now. I acidently went into a DSG while in 'D' and the clever little car shifted it to 'N' for me before it powered down.

I also figured out why DSG exists. Imagine the front axle of a prius is hanging over an over hang with an injured driver jamming the accelerator. Front wheels would be spinning at 100 mph. Since the front axle is spinning a momentary press of the Power button would be ignored. Well the guy who comes up to rescue the injured driver will darn well want those wheels to stop, so the 4-second override was probably provided to turn the car off in case of a crash, assuming that all the brains in the ECU hadn't figured out what happened and powered it down anyways. Kinda a manual override.

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Hi Sup’d:

___The way CAT light off is deduced is through the coolant temp. Some O2 sensor magic can detect afterwards but from what I have read in the past, the manufacturers use coolant temp to infer the CAT “has been lit” (warm enough to convert the nasties to the semi-benign).

___Dan, interesting about a DSG going straight into N after punching her out. There is no disconnect in the Prius so a DSG just removes the fields from both MG1 and 2 but for it to maintain that once powering back on must be your protection idea coming to play.

___Good Luck

___Wayne

___A bit OT but S1 in an NHW10 – 20 design does not necessarily mean it will be in the NHW30 or whatever the next model designation will be? Honda Accord and HCH PZEV’s achieve Tier II/Bin2 and they do not have anything even remotely simulating S1. I hope Toyota follows their path and gets rid of this thing altogether.
I've been watching this thread casually but haven't really studied it. Wanted to wait until I had some time to test the technique in a variety of ICE temps and conditions.

Meanwhile, Wayne, I don't see how they can not make major changes to the warmup process in the plug-in. Sort of defeats the purpose of having a car that makes all your short hops in EV if it automatically lights the ICE early on and, without mods like an EBH and grill block, keeps it on for several minutes.

Hi Jim:

___Yes indeed and that is probably the OEM Prius PHEV-6/7 acted once I hit the “PHEV off/Prius std. mode on” button.

___The OEM’s 62 mph all-EV capability as well as the bar graph depicting the power level and a hard deck when the ICE will kick on is there for a very good reason wrt the PHEV but emissions should not be part of that equation until that ICE actually does have to go live. If someone steps on it hard enough to bring the ICE online, oh boy is this going to be a mess with any kind of S1 program getting in the way. I suspect there are a lot of engineers in Toyota City working on this right now in fact.

___As Dan or Marc pointed out earlier in the thread, you would not want to be heading down the road at 60 mph when the PHEV pack hit its DoD limit and all of a sudden ICE power dies away and you are riding the full but std. 500 Wh (actual) capacity pack in S1 at 60 mph waiting for a CAT light! We can all be assured that will not be the case for the PHEV variant. What worries me however is this S1 warm-up hit coming to play on the std. 09 Prius-III when it becomes available after January 09. The upcoming non-PHEV hybrid could have all of the same mess but I really hope it does not.

___Good Luck

___Wayne

___As Dan or Marc pointed out earlier in the thread, you would not want to be heading down the road at 60 mph when the PHEV pack hit its DoD limit and all of a sudden ICE power dies away and you are riding the full but std. 500 Wh (actual) capacity pack in S1 at 60 mph waiting for a CAT light! We can all be assured that will not be the case for the PHEV variant. What worries me however is this S1 warm-up hit coming to play on the std. 09 Prius-III when it becomes available after January 09. The upcoming non-PHEV hybrid could have all of the same mess but I really hope it does not.Wayne, I may be off my rocker but I think if you floor it at speed the control software will throw you immediately to S2. I say this because I was able to force charge from a cold(ish) engine and the RPMs did go up.

I was hoping for a 90 today, but I'll burn some gas to make sure I'm not crazy wrt S1 breakout at load.

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I'll point out one thing that's going to be true in much of this
experimentation... if you manage to sidestep the bulk of S1 on
a cold engine, and it comes in for real to provide power, that
even if you're "driving gently" the throttle control will bring
the engine pretty much right up to full torque even if it's
low RPM. So that traditional advice about "drive gently to
warm it up" as opposed to sitting there idling is by and large
NOT going to be gentle on the Prius engine. That 57 seconds,
during which you should likely be moving gently on the battery,
is for the good of emissions and a little better thermal
stability before you really start layin' into it.
.
In the already-mostly-warm case, it sounds like messing with
the THW sensor lead [coolant temp] like Bob Wilson was doing
in his NHW11 a while back might be better and more controllable
than all the gratuitous reboots.
.
In my own departure flightplan, S1 is just about long enough
to crawl gently up a small hill leaving my house, go to EV mode
at the crest [if allowable by battery temp], and then coast down
a fair ways and continue a short hill-n-dale EV toggled P&G out
to the main road. At that point the ICE should be plenty ready
to handle a higher load. But for that first climb, I know it's
on battery and I try to limit it to 10 amps.
.
_H*

Hobbit,

What is the advantage to limiting the draw to 10 amps.

It just keeps currents lower for less ohmic heating in the pack
and wires, and avoids drawing the thing way down quickly.
At least I'm *moving* in that state even if not very fast,
and as soon as S1 is over and I crest the hill I kill the
ICE and normal glide most of my way out.
.
_H*

REVISED: The original flawed procedure is quoted in post #5

OK, I'm modifying the procedure to make it as reproduceable as possible.

Get in your Prius II.
Depress brake and power on Prius
Don't put it in gear, just wait 7 seconds for the engine to turn on.
Wait 3 seconds, if the engine does not power off, turn off your prius, wait 3 seconds and return to step 2.
If your Prius did shut off, your in S2 (I think).


Now I don't know if this will work if the block temp is below 40°C, but I've seen this behavior with block temps between 50-60°C.

The first couple of times I tried it, the engine immediately (1-2 sec) shut off after it lit. It never hapend on power up #1 or #2. If seen it using the above procedure on power up #3 and in some cases not until power up #4. Even with 3 seconds of ICE each power cycle and 4 power cycles to get there, it may still burn less gas than a normal S1 burn-in. For now, I'm not saying this will save gas, but getting around S1 is always cool.

I was able to do it twice. Can anyone confirm?

Poll of "confirmed" "not confirmed should follow this post on this thread in 2 minutes.

Oh Specs:
2007 Prius II.
Factory EV mod installed.
Canadian EBH installed.
SG II (no xgauge) installed.
CanView not installd.

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