ScanGage Questions

1 I monitor rpm coolant temp batt voltage and load.
2a Not that I know of the scan gauge can access. The battery voltage
doesn't need constant monitoring, so you can look at other things there like
intake air temp if you add a pre-heat hose.
2b MPG numbers with more digits are useless. They are not that accurate.
I find the scan gauge varies a lot, and I know my mfd read out is very stable.
3 Yes I think sampling rate is the main problem. With longer trips the two mpg readouts get a little closer.
4 MPG readings are probably close above 100 but next to useless. 99 is plenty high to read.
5 MFD always can show engine off when it is on. That is how it works. RPM and the %load on the scan gauge both show when engine is really off. And note there the difference between 0 rpm and off.
6 Believe both. Engine can be using fuel and turning but not supplying power to the wheels or the battery.

 

I have a Classic Prius with a miniscanner, and I normally look at hybrid battery charge/discharge current, hybrid battery SoC, rpm and coolant temperature.. I would love an accurate numeric MPG display vs. the bar graph on the MFD, but the miniscanner doesn't have this data item. I've also got the following items in the in the other view slots of the Miniscanner for quick access: inverter and MG temps, hybrid battery temps, and finally a screen with things like pedal position, power, load..

I use only the consumption screen on the MFD; the energy screen is next to useless except for demonstrating how the car works to a passenger.. IMO, the energy screen is only of use if you're really into that pulse-and-glide technique and looking for the no-arrows state.. I don't drive that way, tried it and didn't like it at all; instead, I feather/reduce pedal pressure for "acceptable" (vs. the very lowest, which is basically what the pulse and glide is trying to continously search for) mileage which is so much easier and still very effective in getting great mileage (47 MPG 5.0L/100km on a Classic in mixed driving). The miniscanner is the key instrumentation in my vehicle..

 

I'm monitoring MPG, voltage (although I don't know why), RPM and one other I don't recall right now. I'm thinking of changing what I look at however. I have an 80 mile round trip commute and I find that the MFD and the Scanguage values for MPG are within "experimental error". The one thing that I was particularly interested in with the Scanguage and which I posted elsewhere here has to do with the "miles to empty" value. If you or anyone else has any experience with the accuracy of this value, I'd be interested to know about it. My latest poster indicates that he has carried extra gas and has run his car down to empty in order to determine accuracy, although he didn't indicate whether this was in relation to this particular value that Scanguage calculates. I'm considering trying this trick and see how accurate the Scanguage value is. Right now it just seems overly optimistic to me. It tells me that my range is around 473 miles per tank. I have gone around 425 miles without running out of gas but the light on the gas guage bar was blinking furiously for awhile. I've read in here that there's another sign of impending doom that replaces this blinking light. I guess I'm going to have to go looking for it... unless someone else has already run this experiment with Scanguage.

 

When Tom mentioned that he was monitoring voltage I also wondered "Why??".. I could understand if you had the Hybrid battery data available, but the 12V status is just a waste of a display line.. The voltage is fixed by the converter and unlike a conventional vehicle, tells you *nothing* about the state of the charging system, so you might as well change that to some other data item..

 

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You're pretty much right, so I did. I changed it to air intake temperature...

 

Reason I monitor voltage is because I like to check my battery regularly. This is easy to do since the battery can be read with the scan gauge before starting the car, if you go to the accessory mode.

Also there isn't much else I want to looki at except hv battery current which this gauge doesn't do. I use it primarily for coolant temp, and for rpm. These are essential.
The load I find interesting but it pretty much tracks the instant mpg on mfd display, with 40 % or less high mpg, and 60% low mpg.

If I add a pre-heat hose again this winter I may switch to intake air temp for a while.
Otherwise I see nothing worth looking at. I looked at Ignition advance a bit, and it was interesting but not that useful for regular monitoring.

 

If you want to pursue this, here's what I'd like it to do:

1 Show the trip, tank, etc % engine run time.
2 Show the hv battery current

That's about all I feel is missing, from my instrument panel.

 

The problem with DTE is twofold. One, the end of the tank is not readily apparent, though Attila has discovered the CAN ID data that gives tank level raw data. It fluctuates wildly, but its peaks decrease as you get to the very end of the tank.
Second, DTE also relies on instantaneous or near average MPG. We all know how much MPG can fluctuate. So, one minute you could have a DTE of 200 since you are driving at 50MPG, but then drops to 50 when your MPG drops, or end of tank volume drops.

Once the last bar blinks, that is your last warning to impending doom, unless you consider 'engine will not start; out of gas' condition to be next IMPENDING doom, since you do still have limited electric drive power. I was able to drive 87 miles of blink at about 52 MPG before running out. I was too far to the next gas station for just battery power, so I called roadside assistance.