My findings on the CAN bus

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I have decoded how to override the time to charge times. It was one of the options I wanted to test. For me the more preferable gauge to override was the temperature. Unfortunately according to the service manual, the temperature doesn't get updated unless the car is moving at least 12 MPH! That will make it difficult to find the proper message...unless I put the car on jack stand and set the cruise to 15mph.. lol

Dude, if I could find how to press agree through CAN I'd be the happiest man alive. I don't understand why on earth they did that. It's so friggin annoying. Unfortunately, it's probably not going to happen.

The VSP, maybe. But its probably easier to disconnect the speaker.
 
garygid said:
A list/display of all 96 cell-pair voltages, and the 4 Pack temperatures would be really great.
I thought I wanted a real-time view of my cell voltages as well. Now that I have it, I find that it's not worth looking at. All I want is an indication of a cell out of range - and an automatic response if it happens. And that's exactly what the Leaf does.
 
Looks like both my ideas aren't going to work.

When I finally thought about it, I realized the charge timer can only go up to "59" before to rolls over to 1:00...so that won't work.

I messed with the ambient temperature today and got nowhere. There is something seriously messed up with it. It read 61 when i started. After messing with some messages, it suddenly dropped to 41. But I don't think it had anything to do with me. I messed with it for another 1/2 hour and it just naturally went up to 43. I gave up and headed home. I went three miles on the highway, and I watched it count up 43,45,48,50, to 53 in a matter of about 45 seconds right after I got off the highway. :?:

Anyway, I haven't given up totally on the temp sensor display, but I don't see any other messages I could "hijack" to display the SOC on the dash...with the exception of the range. But that message gets transmitted quite often so it might be hard to override cleanly.
 
So I completely figured out the temp sensor and I see why it's so inaccurate. I don't think it's that it's inaccurate but it's so heavily dampened it's not even funny.

I found the message with the data. But the service manual says that the temp won't update until you start moving. Yeah this is no joke.

I put a switch with two fixed resistors on it so I could switch back and forth and connected it in place of the temp sensor. I could see the message changing, but the dash did not. Though when I unplugged the test setup with the car still on, the dash went to -25.

I drove around for 20 minutes and it had only gotten up to -6. Then all of a sudden, it started clicking off numbers but stopped at 22. weather.com says it's 53, feels warmer though.

I have a feeling not only is the dampening speed related (and not just "over 12mph", the faster you go the faster it updates), but it also appears to be time-since-start related.

In any case the problem is the message is transmitted in real-time, but the dash is the one dampening it. So that idea is out the door. Seems the only thing left is to make an external display...
 
If we could just "open" the Nav system's OS so that we could add many CAN-Data display screens there.

Does the "special" set of button pushes get us to screens that would be helpful?

I forgot the sequence: something like Menu, Menu, Menu, Map, Map, ... ?
 
garygid said:
If we could just "open" the Nav system's OS so that we could add many CAN-Data display screens there.


Santa, for Christmas this year, I want what Gary just said.

I promise I'll be a good boy if you can deliver.

Signed,

Jimmy
:lol:
 
garygid said:
If we could just "open" the Nav system's OS so that we could add many CAN-Data display screens there.

Does the "special" set of button pushes get us to screens that would be helpful?

I forgot the sequence: something like Menu, Menu, Menu, Map, Map, ... ?
Everybody knows it's Up, Up, Down, Down, Left, Right, Left, Right, B, A!

Here's the actual procedure:

1. Turn the power switch ON.
2. Turn the audio system off.
3. Press the “MAP” switch 3 times. Press the “PWR” switch 2
times. Press the “MAP” switch once.
 
On, Audio Off, Map 3x, Pwr 2x, Map 1x

Thanks.
Does it show us anything interesting or helpful, like temperature?

If the system is powered ON with an SD card in the "spare" socket, the system might look for a special "update" file name on the SD card?
 
Unless that thing is running Linux, I suspect gaining access to it would be not worth it. The only possibility I can see is writing new software for it from the ground up. That's still a huge project!

We've had the same issue in the Prius world.

-Phil
 
It doesn't look like there is anything particularly special in the system diagnostics menu, but the service manual only walks you through upgrading the software...

The screenshot they have shows the following, but the scrollbar indicates they are already at the bottom of the page:

Clock Settings
Delete Unit Connection Log
User Data Initialization
Version Information
Software Update
 
Ingineer said:
Unless that thing is running Linux, I suspect gaining access to it would be not worth it. The only possibility I can see is writing new software for it from the ground up. That's still a huge project!

We've had the same issue in the Prius world.

-Phil

Just do like they do with the Prius. Put in a second mini computer in the car and have it do whatever you want....I'd like to see a better Navigation. Add a switch to swap between displaying the factory screens and the screens from the new mini computer. I imagine that the second computer might just duplicate many of the screens on the factory system so that you don't have to switch back and forth very often.
 
palmermd said:
Just do like they do with the Prius. Put in a second mini computer in the car and have it do whatever you want....I'd like to see a better Navigation. Add a switch to swap between displaying the factory screens and the screens from the new mini computer. I imagine that the second computer might just duplicate many of the screens on the factory system so that you don't have to switch back and forth very often.
Absolute best navigation software I've ever seen is CoPilot from ALK Technologies. (I'm not affiliated in any way.)
http://www.alk.com/copilot/ipad/

Maybe combine nav, energy display, and custom displays onto an iPad?

ipad.jpg


Or maybe take-over the Leaf's display entirely with custom software?
 
turbo2ltr said:
I have decoded how to override the time to charge times. It was one of the options I wanted to test. For me the more preferable gauge to override was the temperature. Unfortunately according to the service manual, the temperature doesn't get updated unless the car is moving at least 12 MPH! . . . . . . . . . . . . . . . . snip
I believe what you actually mean is that the ECU's have to "BELIEVE" that the speed sensors are sending a 12mph signal . . . and I know at least two electrical engineers who has successfully spoofed their Prius into believing said data that is in fact not true.
;)
just a thought
 
It doesn't matter. Yes I could send it a fake speed signal to go along with it (which would show up on the speedo and put miles on your car, who would want that?) but I did even more testing (I REALLY wanted this to work) and found it's just not going to work. The dash messes with the value too much.

The dash dampens the temp more going up than it does going down. So the temp will drop almost instantly, but takes a very long time to increase. There seems to be a time lockout where it will not change for the first 5 minutes after start, then it seems to update a bit faster. It also seems to be speed related. It seems to update much faster above 65.

I ended up replacing the temperature sensor with a fixed resistor for some tests so I could take the actual temperature out of the equation. It took a full 10 minutes before it even got close to the temperature it should have read. and even then, sending fake messages seemed to result in an averaged display, not the number I asked for.

It seems an external display is the way to go. So now the question is, do I come out with something simple and quick or more elaborate that might take longer...
 
evnow said:
turbo2ltr said:
I have decoded how to override the time to charge times.

I can live with that.

Unfortunately the right two digits only go to 59!

I suppose I could encode it as 10:00 would be 100.0...6:54 would be 65.4. Kinda clunky

Edit: I'm an idiot, this won't work either.
 
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