MFD indicates 0 mpg at times! What's going on?

hmmm. I think those error codes might not be as OK as the dealer said?

 

I agree. There's something amiss. I would take the car to the dealer ASAP, explain what you encountered, and have him run another code readout.

 

I've noticed the same thing every once in a while. In fact, it happened today shortly after I filled up with gas.

I did notice that the average MPG was not affected -- just a couple of bars that indicated 0 or very low MPG. Sometimes it will show several regeneration symbols "floating" by themselves in the black area.

I did a scan and there were no error codes.

 

Newbie here, hardly an expert.

I've noted in numerous threads that when weird, unexplainable, seemingly random things like this occur, its frequently the 12V battery making a cry for help just before it dies. Well, not really, it's the CPUs getting less than min electricty.

You might consider having it looked at/tested.

FWIW

 

The only time I see zero bars like that is when I'm standing still. Obviously you get zero mpg if you are not moving, but that doesn't sound like your situation. Do you have any sort of speed sensor defeat installed to allow running the MFD when moving? If you do, I'd check that, otherwise something is fishy.

Tom

 

It seems that I've heard somewhere here on Priuchat that 0 mpg bars are an indication of standing still or no fuel being burned for that period?

 

This happens to me in situations where it definately should not be showing zero -- just normal driving.

 

I certainly hope Japan didnt fall for that deal Bill Gates had for programming!:drum:

 

This may or may not be what is happening here, but I believe that this can occur under normal circumstances. I think its an artifact of the way that the instantaneous mpg is calculated. As I recall, if the ICE doesn't start during a 5 minute period, then it will show 0 mpg even if you have been moving. This can happen even at freeway speeds going down a long down hill. In crawling traffic tends to be another. It sounded like these might have been the two circumstances you encountered, but I'm not sure.

Here are a few related threads:
http://priuschat.com/forums/prius-technical-discussion/37829-black-bars-consumption-screen.html
http://priuschat.com/forums/care-ma...ing/22769-missing-bar-consumption-screen.html
http://priuschat.com/forums/fuel-economy/33594-explain-me.html
http://priuschat.com/forums/audio-electronics/14212-interesting-consumption-screen-bug.html

Rob

 

I am 100 % certain that your explanation is correct. You get them when you experience a full 5 minutes of the ICE not running (not using any gasoline). I once was stuck in traffic at a crawl going to a Browns game, the highway was also going down hill and I experienced solid black 5 minute bars in a row.

 

Your explanation makes sense in the circumstances you are describing. However, I experience this when the car is under normal operating conditions -- with the ICE cycling on and off. It sounds like this is what the original poster experienced.

I have had situations where I would expect a 0 reading, such as waiting in a long line without shutting the car off.

What I experienced today was not normal. I don't know if it's something that can or needs to be fixed, or just an occasional anamoly.

 

The MFD ought to show fuel consumption as gallons per 100 miles (or liters per 100 km); then we would not have these ambiguous situations.

 

i see this all the time and i say you have little to worry about as long as trip MPG's dont change much.

in any situation where you travel a very short distance over time, you will see this kind of stuff. check it out when going thru drive-thrus, traffic jams, waiting to pick someone up etc.

there are times i meet my SO for her lunch and we just sit in car and talk without turning off engine, so i will get 3-4 zero bars and even maybe a 100 mile bar... it all means nothing when you know you have not gone anywhere except across a parking lot.

 

And yet if the car doesn't move, but uses fuel the display would need to display something ambiguous.

What do you display if the engine doesn't turn on for 5 min while the car isn't moving, you would have 0 gallons divided by 0 miles.

How about if the engine does turn on during the 5 minutes while the car isn't moving, you would have X gallons / 0 miles?

 

Again, this happens when the car is operating under normal conditions -- not idling or in stop and go traffic, etc.

Turns out it is the Lockpick. I drove for five minutes and the bar display was normal. For the next five minutes I went to a screen that engages the Lockpick. The second bar showed 0 mpg and there were several regeneration symbols. For the third five minutes I disengaged the Lockpick and things were back to normal.

I guess this is cost of defeating the speed sensor to use the Lockpick functions. Personally I would much rather use the Lockpick functions and put up with an occasional wierd reading on the Consumption screen. I don't think it's really a problem.

 

In the first case I'd say it would be intuitively appealing to display zero gals per 100 miles for that time interval because no fuel was used. In the second I'd say it would be intuitively appealing to display infinity gals per 100 miles for that time interval because the car did not move.

 

I suspect creating the display that would allow such a graph would be cost prohibitive.