Last year I had a terrible time the two days I had a similar idea....but with a sticker on my back bumper so I took it off before anybody got hurt and all is back to normal again.

Your sign may not be a good idea visible up your back side but posted out the rear door driver side window would certainy be game.

I've even thought of hanging a small erasable type cardboard "Baby on Board" sign via suction cup on that rear side window while I drive, but to take it down again after I park..... To keep the keys off the paint.

 

My recommendation is to plunk down the $50 on the "2003-2005 Civic Hybrid Electrical Troubleshooting Manual"

http://www.helminc.com/helm/product2...TPB802SWPAERT6

No guarantee, but it will probably get you where you need to be. what are you going to use for a control unit? A laptop or a custom circuit?

 

Kinda Wonder if People would think we are try'n to make them Jealous!(maybe we are?HeHeHe:-)
As it is many non-hybrid vehicles, especially the Big Trucks, tailgate me in the slow lane and then quickly serve to the left to pass me up, with all 'Barrells' opened up and with a Sneer on their face!(with exception when I have my Postal Worker Uniform on,LOL)

I can't believe all the Hostility I've gotten since the purchase!(HateCrime? Governator Arnold!)

I don't know about place'n that Info. on the rear Winshield...But, it would make a Very Funny Commercial! LOL

 

I actually bought that manual, but they don't get down to the communication-level details. They just mentioned what busses exists and how the panels are powered, etc.

Wish I knew someone at Honda. Any honda software engineers reading this???

 

Hello,

Again, if you know that you can get signals from ECU's, such as injector pulse width and speed pulse, you can get the mileage number.

https://www.greenhybrid.com/discuss/...1-t-1.3015.html

Ken@Japan