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Sudden loss of range and what to do now

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Ah, sorry. The only other thing I can think of is to visually look at the connector under the dash, to be sure there aren't any munched contact pins.

Which connector are you referring to?

As you can see on the picture below, the structure "behind" the USB port is closed – I can't access the wires behind it, unless I start to disassemble those plastic panels. (You can see my unrecognized – but lit – USB drive on the left).

IMG_20200128_183425.jpg


However, I'm concerned because there's a loose harness emerging from the VMS – a connector connected to nothing. You can see it clearly on the left side of the picture below (with only red and blue cables). Do you guys have that too? Could it be that it should be connected to something?

IMG_20200128_183346.jpg


Thanks!
PF
 
However, I'm concerned because there's a loose harness emerging from the VMS – a connector connected to nothing. You can see it clearly on the left side of the picture below (with only red and blue cables). Do you guys have that too? Could it be that it should be connected to something?

That is the diagnostic port. It is not supposed to be connected (unless you are using OVMS). Service Centre uses it to maintain the car.
 
This evening PF stopped by my house so we could try the log dump with the USB drive that I've used all along on my car (it is the TESLA-branded 1GB drive that I got at Menlo Park in 2008). The log dump worked as expected. I was surprised to discover that the USB socket was oriented with the "top" side toward the driver rather than toward the passenger as it is on my car and the few others from which I have collected logs. In fact, you can see this by comparing the photos in the two posts before this.

I also updated the GPS firmware using my cable and the Garmin software running under Wine on my MacBook. That all went very smoothly.
 
All right, so reading those logs...

First, it looks like the pack is quite balanced. No brick seems to deviate much from the rest:

brick soc v
0 737750 32288
1 739196 32289
2 737750 32288
3 731135 32248
4 722845 32209
5 714550 32168
6 722845 32209
7 722845 32208
8 722845 32208
9 722845 32209
10 722845 32208
11 722845 32208
12 722845 32209
13 731135 32248
14 722845 32209
15 731135 32248
16 722845 32209
17 722845 32209
18 722845 32209
19 722845 32209
20 722845 32208
21 722845 32208
22 722845 32209
23 722845 32208
24 722845 32209
25 722845 32209
26 722845 32208
27 722845 32208
28 722845 32208
29 722845 32208
30 722845 32209
31 722845 32208
32 714550 32168
33 731135 32248
34 722845 32209
35 722845 32208
36 731135 32248
37 722845 32208
38 722845 32209
39 722845 32209
40 722845 32209
41 722845 32208
42 722845 32208
43 722845 32208
44 722845 32208
45 714550 32168
46 731135 32248
47 731135 32248
48 731135 32248
49 722845 32208
50 722845 32208
51 731135 32249
52 731135 32248
53 722845 32208
54 714550 32169
55 722845 32208
56 722845 32208
57 714550 32169
58 722845 32209
59 722845 32208
60 714550 32168
61 722845 32208
62 729295 32242
63 739196 32289
64 739196 32289
65 731135 32249
66 731135 32248
67 731135 32249
68 731135 32249
69 731135 32249
70 722845 32208
71 722845 32209
72 722845 32208
73 722845 32209
74 722845 32209
75 722845 32209
76 731135 32248
77 722845 32209
78 722845 32208
79 722845 32209
80 722845 32209
81 697514 32088
82 697514 32088
83 697514 32088
84 714550 32168
85 722845 32208
86 714550 32169
87 722845 32208
88 722845 32209
89 722845 32208
90 714550 32168
91 714550 32168
92 722845 32208
93 731135 32248
94 731135 32248
95 722845 32209
96 731135 32248
97 722845 32208
98 731135 32248

Then the CAC through history. I won't copy all lines since July 2018 but it starts so:

07/20/2018 16:37:12, 156.65, 156.65, 0, 156.99

Decreases relatively regularly and after 4 months:

10/21/2018 10:33:13, 152.27, 153.12, 43, 152.59
10/22/2018 10:33:13, 149.70, 150.61, 43, 150.02

Then 2 weeks later:

11/09/2018 09:56:37, 149.98, 150.90, 86, 150.31
11/10/2018 09:56:37, 146.45, 147.93, 86, 146.77
11/11/2018 09:56:36, 142.52, 144.46, 60, 142.83
11/12/2018 10:28:52, 141.66, 143.71, 60, 141.97
11/13/2018 10:28:52, 142.40, 144.40, 60, 142.71

Stays above 140 for 3.5 months:

03/31/2019 11:01:07, 140.46, 143.66, 86, 140.77
04/01/2019 11:01:07, 139.84, 143.03, 86, 140.14

Then another sudden drop, 5 months later:

09/01/2019 14:16:53, 136.70, 140.18, 86, 137.00
09/02/2019 14:16:53, 133.05, 136.36, 86, 133.34
09/03/2019 14:16:54, 131.23, 134.37, 86, 131.51

And that's last Thanksgiving Day when I ran out of battery in spite of the indicated remaining range and saw the big drop in range afterwards:

11/27/2019 23:33:44, 129.29, 133.80, 60, 129.57
11/29/2019 00:53:09, 121.71, 129.35, 32, 121.97
11/30/2019 00:54:45, 123.53, 130.72, 32, 123.80
12/01/2019 04:50:12, 120.51, 127.30, 32, 120.77

It's been very constant since then and that's the last value.

02/06/2020 21:16:28, 121.42, 128.04, 32, 121.69

So a remanufactured pack went from 156 to 120 in pretty much exactly 1.5 years. That's a 23% loss. Is that supposed to be so?

Also, these big sudden drops... Do you think they're the result of recalibrations somehow? Or of other events?

Thank you for your thoughts!
 
It appears you have a few weak bricks, since, if I''m reading this correctly, the lowest brick has jumped from:
#43 -> #86 -> #60 -> #86 -> #60 -> #32 as the soc continued to fall.

Could be something else going on causing multiple bricks to be at the bottom...

I'll let the battery experts comment as I have limited experience with reading these reports.
 
Up... Any comments from the battery experts among you?
Thank you!

I think the 156 CAC value is not valid and not a true CAC. I think it " POPS" to the high value as soon as the battery is switched, then learns what it actually is.

Mine had a 157 or so after my battery replacement with a refurb. These are used sheets taken from other packs at Tesla and they try to match them as far as levels.

As I drove it, the CAC level fell precipitously as shown in the graph. Not exactly as low as yours but a similar graph. I think it depends on the donor sheets and what their previous CAC level was.



As you can see on 11/2019 I got a referb back and the CAC went from 132 to 157... then steadily dropped to about 135 where I am currently.

upload_2020-2-27_16-2-21.png


I'll see where it is after I get it back from repair and upgrades from Carl @ Medlock and Sons.

Its been 6 months since its really been driven as her nose got sheered off in an accident, so it will be interesting to see where the CAC is now...
 
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