ScanGauge MPG reading when gliding

<div class='quotetop'>QUOTE(Highly ImPriused @ Nov 2 2007, 09:15 AM) [snapback]533813[/snapback]</div>

You again?
Sounds like you and I both got the same (perhaps) bad batch of SG units. Mine does the exact same thing as yours. I reported this to Ron DeLong at Linear-Logic about 3-4 weeks ago. It's an error in how our particular SGII units are reading & displaying MPG. I'll be returning mine for a new one. I suggest you do the same.

 

<div class='quotetop'>QUOTE(Highly ImPriused @ Nov 2 2007, 09:50 PM) [snapback]534179[/snapback]</div>

Should be available now. When I spoke to Ron several weeks ago, he indicated that none of the new units shipping back then had this issue... at least to his knowledge.

 

Dang, looks like mine also has this issue.

Whats the procedure to get it replaced with a unit that doesn't have this bug?

 

Thread back from the dead....

I got the 0.01 GPH glide bug in mine too, and it's relatively new. Got it in May of 08.

Has anyone confirmed that there is a fix for this... ie, did anyone send theirs back and get a good one in return?

11011011

 

Dan,
According to Ron DeLong at Linear-Logic, it's not a bug in the SGII but rather how our particular Prius vehicles are communicating/reporting data to the SGII. In other words, if we took our SGII and hooked it up to another Prius (like a 05 or 06 model year), then our SGII would correctly show 9999 mpg when gliding.
However, I'm thinking there's got to be something that Linear-Logic could do (like another software/firmware update) to address is 0.01 GPH glide anomaly.

 

My 2008 Prius responds the same way, but I've always considered it a "feature" rather than a bug. The mpg it displays during a glide is, roughly, the speed (in mph) times 100. (Example: if it shows 2362 mpg, the speedometer is probably showing 23 mph.)

Peace,
--CC--

 

Alright I've got to call BS on that one. I have two ScanGauge. One (before the XGauge FW) shows glides at 0.0 GPH, the other (with the XGauge FW) shows glides at 0.01 GPH. Hard to argue it's the cars fault if SG reported correctly a few FW rev's ago.

The actual reading on GPH is below 0.01 it just rounds. The real floating point figure is somewhere between 0.0050 and 0.0066 GPH.

11011011

 

Re: Uhh, I Must be Missing Something

Folks,

I've got a ScanGuage, and use it every day. I will admit that I show MPG, not
GPH.

That said, I don't understand how this incredibly small error has any
meaningful, real-world consequence. 1/100th of a gallon of fuel for every
hour spent gliding. In my mostly urban driving situation, that would
represent some 250 or 300 miles driven. Being a less than perfect hyper-
miler, I know that in that distance I over/under estimate times and
distances, fail to hit glides at the exact top of an incline, accelerate to keep
up with traffic vice in "sweet spot" RPM band, and otherwise don't get
absolute max FE/MPG. Oops, there goes at least 1/100th of a gallon for
every 10 miles driven.

Perhaps I'm too cavalier, insensitive, ignorant, laid-back, whatever to
understand what's going on here.

I am willing to learn. So, can someone tell me why I should be concerned
about this condition of less than absolute numerical correctness out in the
second decimal place, or beyond.

 

I have two, one new this spring, the other updated about the same time. Both will sometimes show 0.02 l/hr when the engine is not running. But they will both also sometimes show 0.00 l/hr when the engine is not running.
My conclusion is it's an "undocumented feature" of the Scangauge. It causes no problems that I've seen.

 

Here's an imaginary example to illustrate the point. Imagine you have to pick up a prescription at a pharmacy 1 mile away with a drive-thru window. You reset your FCD and go to get your medicine. You spend 1 hour in the drive thru window because the keep messing up your prescription. When you get back your FCD reads 25 mpg (not bad for a 2 mi trip). Thats 0.08 gallons of gas for the trip. Your scangauge on the other hand will log 0.09 gallons of gas for the trip since you spent much of that hour in EV (sitting at the drive-thru). Your SG will report 23 mpg instead of 25, and will be off by 12%. Now since I spend roughly 25 hours in EV per tank, my GALLONS TO EMPTY will be off by a quarter gallon per tank. MILES TO EMPTY will be skewed by 20 miles. This translates to SG reporting an MPG 2.5% below actual for me on my daily driving.

All in all it's not a OMG kinda error, but it is a glaring one and seems too obvious to just ignore. The code to do this is already in their older FW, they just need to fix the bug.

The bug follows FW 3.15, so if you upgrade an old gauge to 3.15 it will get the bug. The only time I've seen GPH of 0.00 is when running in fuel cut. Whenever RPM = 0000 GPH = 0.01.

Could you help me know what your RPM and KPH values are when your GPH reads 0.00?

11011011

 

Dan,

thanks for the response.

Your imaginary example is not unfamiliar to me. Although after 10 minutes
I'd be inside giving the pharmacist the old "How-come?" and "What-for?"

I guess that I'm just a little too laid back to claim to be a true hyper miler.
For me, that 2.5% gets lost in the noise of daily inconsistencies on my
commute. I can't/don't obsess about it.

Just for the sake of discussion, when you're stopped at the drive-thru, would
it make any difference if you were in park, or neutral? Most folks, me
included, don't have the EV switch. Wouldn't that reduce the impact?

OK, let's say that ScanGuage recognizes the problem and offers a free Firm
Ware fix. Would I then have to send mine back for an upgrade? If so, I'd
probably take a bye.

 

For reference, my previous SGII unit (which had either ver. 3.13 or 3.14... I can't remember) also had this 0.01 GPH "bug". I exchanged this older SGII unit for a new one with ver. 3.15 preinstalled. The new unit has the exact same issue.

Really not a big deal for me. However, it would be nice to see a higher (& more correct) MPG reading on the SGII when gliding.

Presently, anyone who wants a firmware update must send their unit back to Linear-Logic.

 

np. In my job it's imperitive to point out errors whenever you see them. Quality control thing. My view is centered around the word "gauge". If your shopping two gauges, both the same price, would you buy the one that is "97% accurate" or the one that claims to be "99.5% accurate".

I'll have to pull the FW of my current "old" gauge to tell you. But it does show GPH 0.0 in a glide.

Ditto... More correcter is better than less correcter .

Guess I'm hunting for the firmware version 4.00 or some other non-existent (but fixed) release.

11011011

 

I see 0.02 l/hr when not moving and the engine has stopped. RPM=0 Speed=0
I see 0.00 l/hr when moving and the engine has stopped.
RPM=0 Speed= up to 66 km/hr (stealth mode.)

I find it very hard to maintain "warp stealth" long enough to watch the Scangauge, as the "dead band" in the accelerator pedal is so narrow, so I don't know what the reading is in that mode, though I -may- have also seen 0.00.

 

I've tried it while moving before, but I took these from my driveway. Same car, two gauges daisy-chained. One reads 0.01 GPH the other reads 0.0 GPH.


Pulling up the FW revisions. The one with the GPH bug is FW ver 3.15. The one with the "correct" GPH reading is FW ver 3.01.


11011011

 

Interesting. I guess what Ron @ Linear-Logic told me was not quite true. Thanks for running the test to confirm that it is indeed a software bug in the SGII. Hopefully, Linear-Logic will release another firmware to correct this. If not, no big deal. As others have said, the 0.01 GPH bug is more of a minor annoyance.

 

I was looking at GPH today and I think I know whats going on. When I capture data from my can-view there is data captured that I think is the injector timing. This data shows the the injectors stay open even when in EV mode but stuck at a random time. The only time they close is when in a warp stelth.

When looking at GPH on the SGII it will show 0.01GPH in EV but will drop to 0.00 when in warp stelth. I think they are getting their GPH claculations from this injector time.

This is just a guess of mine. I would like to see this fixed sometime soon.