North American EV Indicator Light

Well I just got done tearing my dash apart to see if installing an EV light is possible. I spent 6 hours tearing the dash apart. Had a good learning experience. Cut 3 fingers. Scratched my leather wheel cover but I put some touch up paint on it to hide the scratch. Lost my MPG on the MFD but I was only about 100 miles into this tank. My conclusion is that its not possible to add the EV light. :angry:

I was able to trace down 3 connectors that go to the EV light. I soldered on 3 lengths of wire to the 13 pin connector where I traced the connections too. I then hooked everything up and put my volt meter on the ends of the wires to see if there was a voltage change when I entered or exited EV mode. Sadly nothing changed. I tried all 3 in different configurations. I even tried grounding each wire with the volt meter hooked up. The Only thing I found was 2 of the wires had a constant 12v and the other was a ground.

I believe there must be either (1) There are some more components missing from the main computer (2) There are missing wires going to the main computer or (3) There is no programming for the light.

I'm not going to dive into this any further but if anyone else wants to tackle this you can.

Also if anyone is interested in a schematic of the indicator circuit board just ask and I will post it shortly.

You can see where the EV light should go here on the left right next to the W. The W means the LED should be WHITE.
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<div class='quotetop'>QUOTE(priussoris @ Apr 30 2007, 08:10 PM) [snapback]432861[/snapback]</div>

No icon on the plastic but if I could get it to work I could etch one on.

This would not work because the car could deny EV mode and your light would still be on. Now if Norm could reprogram 1 relay on the Can-View to turn on when in EV mode we could route a light up there but I would not want him to do that because with a Can-View the light is pointless.

 

Well I think I have a theory.

The extra resistor and diode just pass voltage to a pin on the connector. Could this be an "enable LED" signal for the computer? Something like if signal is + then you have EV and light the LED when EV mode is activated, if not dont send voltage to the LED.

Could this be how it works? If so we will need to find the resistor values to give it a try. Maybe if we can get one of our Japanese or Europe guys to take a good pic of the board it might help us a little.

Here is a schematic so you can see what is going on.

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<div class='quotetop'>QUOTE(Tideland Prius @ May 1 2007, 12:13 AM) [snapback]433046[/snapback]</div>

Really? You have the icon? on my 06 it is totally blacked out.

 

I'm fairly certain that the resistor diode combo is there to let the computer know that there is an EV light. I see no other purpose for it to be on this circuit board to be other than an indicator that "something" is installed.

Here is what I would like to do if I ever decide to tackle this again.

Solder the 3 wires back on the connector. Hook everything back up. Run the wires to a bread board. The bread board will have a simulated complete circuit that has say a ~250ohm resistor and LED, and a ~500ohm resistor and diode hooked together as shown in the schematic. Then test to see if the LED will light up when entering EV mode.

Maybe someone that has all this stuff would be willing to try this out.

Also what would help fully understand the resistor/diode combo would be if one of our Japanese or Europe friends could desolder the connector pad that these two components go to then hook everything back up and give it a try. I say desoldering the connector solder pad would be the easiest because its a big pad to solder so you really cant mess it up. Just desolder, test, then resolder. I would do it in a hart beat if I had access to a EV enabled Prius.

 

<div class='quotetop'>QUOTE(Tideland Prius @ May 3 2007, 01:51 AM) [snapback]434568[/snapback]</div>

This could be useful if we can get the light to work. If the 04-07 plastic cover is the same size and shape then we would not have to etch an EV car on to that plastic cover. All we would have to do is get a direct replacement.