Hacking into Zoe's CANbus

[jmeijer]

So, you think it is because you padded the request? That is strange and should not be necessary. But I have seen it done I must confess. CanZE does not do the padding. Maybe the length field in the raw CAN message is not properly send? Anyway, it works and that is what counts. Congratulations!

[Jacky87]

Hello everyone, I am a student of telecommunications engineering, I am realizing an Android app to retrieve some data from the control unit of the Renault ZOE, particularly those regarding battery power. Could you please give me some information about it? between the various obd you have used, which one you think is better?
The APP is great, but it does much more than what I need Which part of the program deals with fetching battery data ?
Thanks for the work done, and for any response.

[jmeijer]

Dear Jacky87,

You have to be a lot more specific. There is not a lot you can "strip" from CanZE, as large parts deal with with fetching data in general. If you are modestly experienced with Android Studio / Java I think you will find which parts you can remove.

Furthermore, there is nothing like "the control unit". There are 16 ECU's in the Zoe! And what do you mean with battery power? State of charge? Voltage? Current?

You can send me a PM if you want to discuss this further, maybe this is a bit too technical for this forum thread.

J

[most]

Hi Jay (hope you don't mind, Jeroen ),

after playing with CanZE with a rented Twizy, I finally got my own Zoe , a brand new R240.
And again, I am playing with CanZE. It is a really great program.

Anyway, I do have one humble request:
I found the 12V Battery's voltage only in the Charge-Screen (more occasionally ). Do you think it might be possible to display the 12V-Battery's actual voltage readout somewhere prominent? I'd like to watch it during driving, and I found myself using the Consumption screen most of the time.

Proposals:
1. Consumtion screen. Forgive me being selfish But this really is where I would love to see it (maybe header right side?!)
1. Battery Page. I'm aware that this page is dynamic whereas the 12V voltage is more static. Anyway the subject fits, I would expect to find it there, assuming I would not know the app.
2. Driving Info. The screen offers plenty of real estate - why not add a line here?

All I'm asking is that you please consider it.


And I've got one question: What is the Instant Consumption (2nd line of the Consumption screen) actually showing? I could not find a connection to the Zoe's computer "Momentanverbrauch" (main dash, right side). Even when recuperating, that Instant Consumption displays values >0 whereas I would expect <0.

Vielen vielen Dank für die wirklich super APP!!!

Grüße,
Matthias

[jmeijer]

Hi Matthias,

First of all, thank you for your compliments. It's what keeps us going!

Second, congratulations ons having a Zoe now! Mine is now 2.5 years in my possession and I like her a lot. She still feels like a new car somehow!

I agree that the consumption screen is really quickly evolving in THE screen to monitor. When "learning to drive" the bars at the top are really helping, especially with braking. After a while, the middle graph is a great help.

Too funny about the consumption question. I have had comments that CanZE was no under-the-hood at all and simply redisplaying what was on the dash The second bar is the power (in kW) divided by the speed (km/h). That may sound crazy but some math over the units will show it's usefulness: kW/(km/h) = kWh/km -> Real consumption as in: how much does a km really cost?

The second graph shows exactly the same value graphed in time, the only difference being the values are a bit dampened with a low pass filter (which is why it only slowly responds to regeneration. It really dips under 0 but it was too crammy to reserve room for that on the graph).

I understand your 12 volt question (the "what"), but at the moment I fail to see the "why", especially while driving. That's no criticism, it's an honest non-understanding. I do agree a logical place could be the battery screen, or the voltage heatmap?

[most]

Hi Jeroen,

the why is simple: I have read quite some threads about the 12V battery being dead at some point in time, one driver even reported that he always has a voltmeter plugged into the 12V outlet.
What really kicked me off: I changed the dashboard design with the button right of the screen recently. Since I did it in the evening, it was only until the morning when I realized that the "booting sound" was different, more like a whistle without any bass. Even the indicator sounded very sketchy to me.
I must admit I got a bit nervous, almost waiting for a "check elect system" message ... that was until I realized that this came with flipping through the screen designs. Believe me: I almost sh** my pants, as I had planned a longer trip that day.

This was where I wanted to check the voltage with CanZE and at first couldn't find the voltage nowhere. This made me ask you if you feel it should be displayed somewhere more handy.

Maybe others would appreciate that, too? Hey Leute, jetzt seit Ihr gefragt!

tnxx
Matthias

[jmeijer]

Haha, OK, got it. Actually, I have had a flat 12 volt battery myself, once, a few months ago. I understand the issue and I will see if I can do that in a somewhat logical way.

Having said that, I truly doubt it would help. Here is my take on the flat 12V (I am pretty sure that is what happened to me).

Car on charger, but plug was not properly inserted, ar a flimsy contact on the CP or PP pin. Car does not charge, and the car stays "awake" as it is trying to lock the plug over and over again (you can actually hear this, kind of zzz-zzz----- zzz-zzz----). The car being awake with all electronics on pulls a few amps. After a few hours in the cold, it was done. Note that the 12 volt is not being recharged in this mode from the traction battery.

No voltage meter would have helped. I think it is a design issue. First of all, the car should stop trying to lock the plug after i.e. 10 attempts; it won't succeed and it's only damaging the (expensive, over 500 euros repair) mechanism. Another problem is the car drains the battery to 5V. That destroys the battery in a few days. Luckily I diagnosed the problem in a few hours and had it on a 12 volt charger quickly.

This is no dismissal of your request. Just saying it is probably not the solution to quickly find a problem.

Learning point: always wait until the car really charges, and when (as is in my case) the charger starts late as mine is tied to economy rates, check when going to bed.

[most]

Yeah, got your point as well. I just guess that checking from time to time might be a good idea. Unless, if there's a way to record it over time and to display a graph - but the sheer figure would do. I guess observing it over a couple of months might avoid a situation that Zoe tells me one day "It's dead, Jim"
Well, I'll just stay put what you guys do with CanZE! It's anyway a great tool since quite some time now.

[jmeijer]

See https://github.com/fesch/CanZE/issues/333

[most]

Sounds great, but I'm not sure if I understand this. So, on github you're asking for feedback before implementing it? Or is there this update already available and I'm just too stupid to find it?
Anyway thanks for considering my wish! Almost x-mas!!