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Posts: 1993
Joined: Mon Jul 19, 2010 8:34 pm
Delivery Date: 12 May 2011
Leaf Number: 002191
Location: San Jose, CA

Re: Active EV-CAN sampling: cell voltages, pack temperatures...

Thu Feb 08, 2018 3:50 pm

hubaksis wrote:Hi everyone,
I think this is the best topic to ask.
I found out that some values can be requested from a module only after setting it into diagnostic mode by sending a command 02 10 C0.

However, I can't find any details about this mode.
Can you tell me, does it have any expiration time? If so - is there a command to keep it active or just send another one 02 10 C0?
Do I need to exit diagnostic mode after I finished all requests?


I think it exits in about 1-2 seconds. 02 3E 01 will keep it alive if sent once a second. No harm in not exiting. It will timeout anyway.

Posts: 1
Joined: Wed Oct 25, 2017 6:16 am
Delivery Date: 25 Oct 2012

Active EV-CAN sampling: cell voltages, pack temperatures...

Wed Jul 04, 2018 1:57 am

Hello all,
Can some one post the request codes for VIN, DCQC count and L1/L2 count of 2012 leaf? I have already tried the 797 but not getting any respond on 079A.
Thank You.

Posts: 1
Joined: Mon Mar 25, 2019 1:47 pm
Delivery Date: 25 Mar 2018

Re: Active EV-CAN sampling: cell voltages, pack temperatures

Tue Mar 26, 2019 12:37 pm

GregH wrote:
garygid wrote:One long set of data from the BMS should be the estimated
cell (pair) resistances, derived from noting how much the
cell-pair's voltage sags when current is being withdrawn.

There might be another set of data indicating charging
resistances, derived from how much the voltage rises
when charging.

There are some odd sets of 10 x 16bit data in group 5.. no clue yet.
Also I'm guessing we might find some sort of counters in there for charge events so that the Nissan battery report can tell how often you've been plugging in at high states of charge or how often you've used QCs..

garygid wrote:Perhaps use F (x 10, so in tenths) = (C x 18) + 320
to display the battery temperatures?

It is increasingly looking like Nissan is NOT using a look up table for the non-linear NTC values but rather a set of linear approximations.. (edit-maybe)
So yes in the range of 18-24 degrees it looks like 10 steps per degree C.. but in looks like in the 12-17 degree range it's closer to 10.5 steps. I'm still filling in my temperature data table.. so far I have the following for temp transitions..

13 degrees starts at 589
14 degrees starts at 579
15 degrees starts at 569
16 degrees starts at 558
17 degrees starts at 548
18 degrees starts at 537
19 degrees starts at 527
20 degrees starts at 517
21 degrees starts at 507
22 degrees starts at 497
23 degrees starts at 487
24 degrees starts at 477
25 degrees starts at 467
26 degrees starts at 457
27 degrees starts at 447
28 degrees starts at 438
29 degrees starts at 428
30 degrees starts at 419
31 degrees starts at 410

<edit> If anyone has data below 13 or over 30, please share! :)
(btw as soon as the highest temp clicked over from 468 to 467, the 6th temp bar on the dash lit up. After resting it has gone down to 468 (24.9deg) and the 6th bar went away..)

probably Nissan connected an NTC thermistor in series with a fixed resistor, and sent the result to an ADC which is what you're seeing.
this is the proper way to do it but they might not have known:
https://en.tdk.eu/download/531110/a3be5 ... nnotes.pdf

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