DBMandrake
Posts: 147
Joined: Mon Mar 20, 2017 4:57 am
Location: Scotland

Re: not charging my iON, cell or CMU or BMU problems

Wed May 15, 2019 8:12 am

kiev wrote:the cell numbering layout chart that Rupert used (referenced on the speakev forum) is incorrect. i posted a correct version here:
viewtopic.php?f=23&t=3943&p=38824#p38832

the most negative, CMU01, is in the right rear corner of the pack, not at the service plug.

Are you certain ? :?

Because if he had misidentified the modules then replacing the wrong CMU would not have fixed the problem with invalid voltages being reported...yet CMU_08 is now reporting valid voltages again after being replaced. That suggests to me that his layout is correct.

I agree that CMU_01 is most negative. The way we worked this out is to compare the bus bar routing in the pack with the location of the two 4 cell modules - according to Diagbox modules 6 and 12 are the 4 cell modules.

As this is an asymmetric configuration (one 4 cell module near the middle of the string and one at one end) there can be no doubt about which is the correct numbering direction - the end of the pack with a 4 cell module must be CMU_12. This connects to the positive output terminal therefore CMU_12 is the positive end and CMU_01 is the negative end.

So as far as I can see the diagram that Rupert and I derived is correct.

Can you explain how you derived your layout ? Your layout is inconsistent with the routing of the bus bars to the 4 cell modules.
- Simon

EV: 2011 Peugeot Ion
ICE: 1997 Citroen Xantia V6

tinoale
Posts: 39
Joined: Wed Apr 23, 2014 6:36 am

Re: not charging my iON, cell or CMU or BMU problems

Wed May 15, 2019 1:53 pm

Well, I have proceeded with the CMU10 board swap, and it worked flawlessly :D
I swapped a CMU10 board with another CMU10 board from eBay.

Nothing visibly wrong with the old board, no matter how close I look, could be the analog-digital converter as pointed out in this thread...

Car is good as new again 8-)

Thanks for all the excellent info provided here :ugeek:

kiev
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Contact: Website

Re: not charging my iON, cell or CMU or BMU problems

Wed May 15, 2019 7:07 pm

DBMandrake wrote:...
Can you explain how you derived your layout ? Your layout is inconsistent with the routing of the bus bars to the 4 cell modules.


It was several years ago that i worked this out using photos from dani's pack dissection, plus the initial incorrect cell identification made by Martin in his video when swapping out a bad cell. More recently i think this has been confirmed by correct identification and location of CMU10 by both tinoale and gary12345 in this thread.

Here is dani's photo of the main contactors showing the buss bar link for the (-) contactor going to the right rear corner module, and the buss bar link (+) contactor and pre-charge contactor going to the 4-cell module on the right side of the car.

Image

ref: former member Dani's thread, Wrecked i-MiEV Battery Pack Discussion, see page 2, post #19
http://www.myimiev.com/forum/viewtopic. ... =10#p27408
Last edited by kiev on Thu May 16, 2019 6:02 am, edited 1 time in total.
kiev = kenny's innovative electric vehicle

kiev
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Re: not charging my iON, cell or CMU or BMU problems

Wed May 15, 2019 8:47 pm

DBMandrake wrote:...
Because if he had misidentified the modules then replacing the wrong CMU would not have fixed the problem with invalid voltages being reported...yet CMU_08 is now reporting valid voltages again after being replaced. That suggests to me that his layout is correct.


Of course i could be wrong about all this--there is so much that we don't know.

i don't know how to explain this, but i suspect that the CMU # is also stored somewhere else on the board, maybe in some memory register of the microcontroller chip.

Using my pack/CMU layout:
If he received a true CMU 08 board, but swapped his 02 board eprom onto the board for the swap, then the replacement board might be responding as if it were number 08 with the good cells that were in module 02. Canion might be able to show that the invalid voltages are still present, if it doesn't get confused by having two CMU 08 boards trying to respond.

Here's a test--try to read the CMU 02 cell voltages. [edit: using Canion if possible]
Last edited by kiev on Thu May 16, 2019 6:59 am, edited 2 times in total.
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DBMandrake
Posts: 147
Joined: Mon Mar 20, 2017 4:57 am
Location: Scotland

Re: not charging my iON, cell or CMU or BMU problems

Thu May 16, 2019 1:21 am

Duplicate.
Last edited by DBMandrake on Thu May 16, 2019 2:23 am, edited 1 time in total.
- Simon

EV: 2011 Peugeot Ion
ICE: 1997 Citroen Xantia V6

DBMandrake
Posts: 147
Joined: Mon Mar 20, 2017 4:57 am
Location: Scotland

Re: not charging my iON, cell or CMU or BMU problems

Thu May 16, 2019 1:25 am

DBMandrake wrote:
kiev wrote:Here is dani's photo of the main contactors showing the buss bar link for the (-) contactor going to the right rear corner module, and the buss bar link (+) contactor and pre-charge contactor going to the 4-cell module on the right side of the car.

Hmm, you've got me wondering now. If I was dealing with a dissembled pack first hand I could figure it out very quickly by tracing from the output of the pack backwards, but I still can't tell for sure one way or the other from piecing the various photographs together. :(

kiev wrote:Of course i could be wrong about all this--there is so much that we don't know.

i don't know how to explain this, but i suspect that the CMU # is stored somewhere else on the board, maybe in the microcontroller chip.

Earlier in the Speak EV thread is a link to this German forum post:

https://www.goingelectric.de/forum/view ... 6&start=60

If you translate it you'll see that BenJX claims to have read the EEPROM contents from his old board and written it to the new board to reprogram the Canbus ID. So until proven otherwise I think we can assume that the identifier is in this EEPROM.

I don't recall where I read it but I don't believe the version of the main microcontroller used has any EEPROM storage in it.
Using my pack/CMU layout:
If he received a true CMU 08 board, but swapped his 02 board eprom onto the board for the swap, then the replacement board might be responding as if it were number 08 with the good cells that were in module 02. Canion might be able to show that the invalid voltages are still present, if it doesn't get confused by having two CMU 08 boards trying to respond.

Here's a test--try to read the CMU 02 cell voltages.

As far as I know he received a CMU_08 board, however he swapped the EEPROM over from the old board. So there are a few possibilities:

1) If the CMU removed was really CMU_02 and the code is in the EEPROM the new board will now be reporting as CMU_02 and there will be no clash between board ID's, however the fault with CMU_08 would remain. Before disassembly CMU_08 was reporting completely invalid voltages (hundreds of volts per cell) but it is now reporting about 3.775 volts per cell. However it is also reporting that 7 of the 8 cells are "under voltage", which we can't explain at the moment.

2) If the CMU removed was CMU_02 and the code is not in the EEPROM, then we now have two CMU_08's in the car. This might explain why CMU_08 now gives voltage readings (from the wrong cells) however.... the BMS is only reporting faults on CMU_08 - and only under voltage faults. If CMU_02 was now "missing" due to duplicate CMU_08's, the BMS would be reporting a fault with CMU_02, but it isn't.

3) If the board removed was CMU_08 then we have the correct CMU_08 in the CMU_08 location and the voltage readings of the cells are real, however the "under voltage" reported in standard parameters measurement of CMU_08 which is setting a cell under voltage fault in the BMU is preventing the car from charging. But why is under voltage being reported simultaneously with all cells reporting around 3.775 volts ?

See the zipped diagnostic reports from post 48: https://www.speakev.com/threads/c-zero- ... st-2615428

(You'll need to translate the PDF's from French using something like https://www.onlinedoctranslator.com/ )

In global test 2 taken after the board swap and all faults cleared the BMU only has faults for CMU_08 set. Fault codes in the BMU are P1A7D "Failure of the voltage sensor cells of the controller of the traction battery 08" and P1A59 "Cell defect of the controller of the traction battery 08", "the default low voltage characterization". This despite CMU_08 reporting all cells around 3.775v.

So where does this leave us ? I'm getting really confused now...
- Simon

EV: 2011 Peugeot Ion
ICE: 1997 Citroen Xantia V6

kiev
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Re: not charging my iON, cell or CMU or BMU problems

Thu May 16, 2019 4:47 am

It appears that Rupert printed out the lower 256 words of the eprom, but the datasheet indicates room for 512--i wonder what was in the upper block, if it were blank or had some data?

In his arduino code, ADW needs to be 9 instead of 8, in order to read out the upper block. Looking at the data, i think seems to show 4 rows of similar data (it repeat 4 times) in the lower block; i would guess there will be 4 rows of repeats in the upper. This may be a row of calibration data or upper/lower limits for parameters for each cell. i will post this over on the speakev forum.

i'll have to do some french and german translation to read the other threads and test reports.


edit, notes on DTCs:

P1A7D CMU08
The signal is received from the appropriate module CMU, which shows that one of the battery cell voltage has an invalid value.

P1A59 CMU08
The battery cell voltage is less than 2.3 V.

These are BMU trouble codes that the global test was reading as passed thru to the EV-ECU. There are 2 CAN busses, one from the EV-ECU to the OBDII connector that talks to the MUT, the other between the BMU and the CMUs. The MUT can access both, but voltages reported by the EV-ECU use a different set of CAN PIDs than those reported by the BMU. So it is not clear which CAN PIDs were used to read the 3.775 volts, versus the fault code showing less than 2.3 V.
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DBMandrake
Posts: 147
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Location: Scotland

Re: not charging my iON, cell or CMU or BMU problems

Thu May 16, 2019 1:51 pm

kiev wrote:It appears that Rupert printed out the lower 256 words of the eprom, but the datasheet indicates room for 512--i wonder what was in the upper block, if it were blank or had some data?

In his arduino code, ADW needs to be 9 instead of 8, in order to read out the upper block. Looking at the data, i think seems to show 4 rows of similar data (it repeat 4 times) in the lower block; i would guess there will be 4 rows of repeats in the upper. This may be a row of calibration data or upper/lower limits for parameters for each cell. i will post this over on the speakev forum.

Thanks for posting on speakev. :) As he has the pack out again at the moment now is the time to figure all these unknowns out and hopefully as well as get a successful repair, document and confirm some points that we're currently unsure about so that future people attempting similar repairs have solid info to work from.
i'll have to do some french and german translation to read the other threads and test reports.


edit, notes on DTCs:

P1A7D CMU08
The signal is received from the appropriate module CMU, which shows that one of the battery cell voltage has an invalid value.


P1A59 CMU08
The battery cell voltage is less than 2.3 V.

These are BMU trouble codes that the global test was reading as passed thru to the EV-ECU. There are 2 CAN busses, one from the EV-ECU to the OBDII connector that talks to the MUT, the other between the BMU and the CMUs. The MUT can access both, but voltages reported by the EV-ECU use a different set of CAN PIDs than those reported by the BMU. So it is not clear which CAN PIDs were used to read the 3.775 volts, versus the fault code showing less than 2.3 V.

The 3.775 volts is being retrieved directly from the CMU's I believe.

To access them you go into the specific CMU in Diagbox and then go to "standard parameters measurement" which is the normal way to retrieve live data from any ECU using Diagbox.

Standard parameters measurement in the BMU does not show all individual cells voltages but does report the minimum and maximum cell voltages as well as the number of cells which are at minimum or maximum voltage.

The CMU's also have a status section that includes whether the voltages are normal or abnormal low or abnormal high, and on the suspect CMU 7 of the 8 cells report abnormal low despite simultaneously reporting 3.775 volts +/- 5mV on the standard parameters measurement screen.

The CMU's do not seem to store fault codes as there is no option to read or erase fault codes in the CMU - the fault codes are all reported by the BMU which does have an option to read and erase fault codes.

I also have a Diagbox diagnostic tool for my Ion so I'm able to take measurements from my working car using Diagbox if it helps, and I've already compared Ruperts Diagnostic results to my own car. From what I can see although functionally equivalent in general, Diagbox and MUT-3 do not have identical feature sets and the user interfaces are very different. So not all features or measurements may translate from one to the other.
- Simon

EV: 2011 Peugeot Ion
ICE: 1997 Citroen Xantia V6

coulomb
Posts: 168
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Location: Brisbane, Australia

Re: not charging my iON, cell or CMU or BMU problems

Thu May 16, 2019 10:07 pm

DBMandrake wrote:
coulomb wrote:I've been reading the CMU firmware. ... In fact, it seems to me that this happens automatically any time that there is a certain type of error (I can't be certain about what type of error, and it was some time ago I that I found this).

Automatic numbering like this seems unlikely - by what mechanism would they acquire consistent numbering when they left the factory ?

If I'm right, they acquire their IDs, possibly every time they are reset, by their position in a daisy chain of special signals for that purpose:

Image

I'll be the first to admit that the details on this drawing are staggeringly light. It's a study in minimality.

So there is this packet that is handled by Uart1 on the CMU processors, with 5 bytes; some sort of packet ID in the first byte, three special bytes, and a checksum of these three bytes in the last byte. Somehow, the number of zeroes in this packet determines the CMU ID. There is a table with an offset (0, 1, or 2 for the second, third, or fourth bytes respectively), and a mask that is one of 0x3, 0x0C, 0x30, or 0xC0. So pairs of adjacent bits are used; if the mask ANDed with the appropriate byte of the packet is zero, then this entry in the table determines the ID. My guess is that the CMU after "grabbing" an ID adds another pair of zeroes and sends it on to the next CMU. The third byte in the table (after the index and mask) is the CMU ID. I note that the entries in the table are ordered 7 8 9 10 11 12 1 2 3 4 5 6. So presumably the daisy chaining of this special CMU ID signal doesn't follow from most negative CMU to most positive, it starts in the middle with CMU 7.

If CMU_03 on my car is in a different location to your car how does that help with diagnostics ? :shock:

Sure, that's no good for anybody. But if I'm right, that will never happen. And copying of EEPROM contents should not be necessary, at least for the purposes of getting the CMU IDs correct.

I'm sorry to say that I haven't found any code yet that seems to be reading the EEPROM. There is a hardware device in the processor called the Clocked Serial Interface, which can handle the required 16-bit serial "characters". But it doesn't seem to talk to the EEPROM, at least at this stage.

There appear to be programming pads for the eeprom on the boards - much more likely that as the board is assembled on the production line a pin probe is attached to program the Canbus ID's.
Certainly, important data is written to the EEPROM when the CMUs are manufactured. My speculation is that calibration constants may live there.

Check the speakev thread I just linked to - Rupert was able to dump the contents of the eeprom which holds the Canbus numbering and while he wasn't able to overwrite it (yet) we think that's just because he forgot to erase the cells before writing them. :oops: Physically moving the old eeprom onto the new board is another approach though, which is what he has successfully done.

Fascinating stuff; thanks for the link. I'll be watching that SpeakEV thread.

I've seen a list of BMU connector signal names somewhere; perhaps from a hand written piece of paper, perhaps from @Kiev. If anyone can point me to it, I'd be most grateful.

kiev
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Re: not charging my iON, cell or CMU or BMU problems

Fri May 17, 2019 2:31 am

Input and output pin configuration of BMU connector:

A is [1-26], and B is [1-22] 31-52 connector C-109

1 Auxiliary battery power source
2 EV-ECU control power source
3 BMU earth
6 CAN interface (high)
7 CAN interface (low)
8 K-LINE
12 Main battery cooling fan relay
13 Main battery cooling fan PWM signal
21 Input signal for main battery cooling fan speed

31 Applied voltage for main battery current sensor
32 Main battery current sensor (high)
33 Main battery current sensor (low)
35 Main battery earth leakage sensor
37 Local CAN (for main battery) interface (high)
38 Local CAN (for main battery) interface (low)
42 Main battery current sensor earth
43 Main battery current sensor earth(shielded)
46 Main battery earth leakage sensor pre-check signal
48 CMU ID automatic number input signal
49 CMU ID automatic number output signal

BMU "learning value"
If replacing the BMU, write the BMU learning value.

When the BMU learning value cannot be saved or when the battery for the auxiliary is removed for more than month, these procedures must be handled. Do not handle those for any other purposes.

1.Check the label attached to the main battery from the left rear wheel to check the manufacturing date.
note
Depending on the manufacturing date, the label may not be attached. If the label is not attached, check the production timing from the vehicle number to regard it as the manufacturing date of the main battery.
2.Calculate how many months elapsed from the next month of the manufacturing date of the main battery to this moment.
3.Connect the M.U.T.-III to the diagnosis connector with the electric motor switch in the "LOCK" (OFF) position.
4.Turn the electric motor switch to the ON position.
5.From the System select Screen of the M.U.T.-III, select the "BMU".
6.Select the "Special Function" from the BMU Screen.
7.Select the "Write learned value (change ECU)" from the Special Function Screen.
8.Select the "Manual writing" from the Write leraned value (change ECU) Screen.
9.Input the number of month calculated in the Step 2 to the "Sum total time back up (month)" from the Manual writing Screen. Write the BMU learning value.
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