MPG read out on my back bumper - how to make that happen?

LOL, funny idea Get a KIWI PLX OBD2 with MPG display and stick it to the lower rear window. Price is about $90 or so. If the 7-segment LEDs are too small for your purpose then disassembe the unit and rewire some large 7-segments in blue color(there are some very large ones available) to it. That would really be funny.

 

that is funny!

the friend of mine had a 70MPG license plate on his Ninja 250. Beats me how he could get 70MPG on his 250, I was only averaging 68-69.

Maybe a 50MPG bumper sticker?
50 MPG Patriot (bumper sticker) from Irregular Times

 

FWIW, this is a bad idea. Anything that runs the risk of distracting another driver could cause an injury or worse. Unlikely, but I couldn't do it knowing that someone w/kids in the car or another driver could do something stupid. You've heard and seen the stories of people who have secondary accidents when seeing police lights and don't pay attention to what's in front of them. This display you proposed would be a dynamic item showing changing #'s which would cause a fixed and maintained gaze while the stats change versus a quick look at a bumper sticker. A personalized bumper sticker seems like a great and cheaper idea instead. My $.02

 

No, such displays do not have any remote outputs or so. Cutting the exisiting 7 segements may not be easy as they might be soldered onto the pcb. But remember you need to wire 3x 7 wires for the LEDs plues 1 wire for the dot plus 1 wire for the common ground. So this is 23 wires from the pcb to the larger 7-segments. Using a flatband wire like the ones inside computers may work if you're experienced with desoldering (the current segment leds must be removed as the driver is possibly not able to drive more leds) and soldering the wires. You don't have to worry about shielding, interferences or so as the signals are low current (ok, depends on the huge sized 7-segment leds you want to use) and without any high frequency. Therefore you may run the flat wires easily underneath the carpet. Keep us updated

 

Naaah, don't paint it too black. Even with a larger size people will only able to see it at a stop. And even then it looks like a static display showing a number to the one behind. If it will show current MPG the display will show -- during a stop what makes no sense. Therefore it's just a funny thing I'd laugh if one would have that in front of me. BTW, showing something like numbers or any other display in direction of any other people on the street is illegal in Europe (ex. truckers often have a display with their CB call names facing to the fronts. Illum them at night is forbidden).

 

I like the KIWI PLX OBD2 with MPG device, and hooked up to some big 7-segment displays would be kind of cool. I think it would be illegal to drive with it switched on though.

 

You are missing the downside here, public stupidity.

You can say you get 50mpg, and have a readout that proves it, but they can go 500 miles on a single tank of gas. Wait you say, how is that equivalent? It isn't, but the general populace doesn't know or care. They say they also get 40-50mpg on the highway, which we know is mostly untrue or just a downright lie. But the car commercial says so, so that must be what they are getting all the time everywhere.

All this will do is make it so that when you are accelerating (or even going slowly not in S4) will have a display that reads 8mpg or 12mpg or something like that. Billy Bob in his hummer will see that and tell all his friends that Prii only get 8-12mpg, why would anyone buy that.

 

You might want to check the legality off this device. Like has been said distracting others might be potentially harmful. I know in Michigan, that you can't have things that distract like neon lights under the car.

 

Here is an idea. Get one of those 7" no name Android tables from Sears or KMart for $129. OBDII Bluetooth adapter for $29 from ebay and a software app called Torque from the Adroid market. Here is a screen shot I took after I read your post.



I have it set to show instant MPG and average MPG. The instant MPG shows 255MPG when the ICE engine is not running.

 

You have the problem of Prius hate over there in USA. Do you want to increase it even more??

 

I'm more interested in a display that shows different driving and braking modes on top of the MPG. The perfect rear display would have 2 infos; Mode on the top and MPG on the bottom. This will work great as license plate frames.
For the Mode I want it to show; Regen Braking, Friction Braking, Engine Off, EV and Hybrid.
For MPG, when vehicle is completely stopped, it shows the average MPG. When the vehicle is moving, it shows the instant MPG.
The display would use red LEDs and dims with the lights. It would connect to OBD-II port and 12v power source.

Few examples when driving
MODE:____________EV (appears when in EV or stealth regardless of EV mode or not)
Instant:_____2045MPG

MODE:________Hybrid
Instant:_______89MPG

MODE:__Regen Braking
Instant:_____1256MPG

when stopped
MODE: ____Engine Off
Average:______65MPG

 

Just because an item sold does not have claims of "not legal in . . . " does not let the seller off the hook. It is up to the buyer to know the laws in his region.

 

i don't know if anyone but another prius driver would understand all that info on your bumber!

 

Who cares if they don't understand. The information is not critical but it shows hybrids have different driving and braking modes. In time people will know.

 

I got one word SMUG, people will just get annoyed and hate us more.