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

Posted: Fri Jan 19, 2018 8:08 am
by kiev
By "digital component" do you mean the LTC6802 chip shown in this photo, or are you talking about the microcontroller or CAN buss chips? The LTC is a generic part and could be de-soldered replaced with a new one.

Inspect all those little yellow chip capacitors for cracked solder joints or cracked body--they are prone to cracking and they short out when failed. Trying heating or cold spray while monitoring to find a defective part.


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

Posted: Sat Jan 20, 2018 9:33 am
by czalbert
Dear kiev. Thanks your advices, I try find somebody who can replace the LTC and fix the board.

But now I have a new solution. I found a used board. Just I don't know, is it programming for 10th block. If don't how can I do that?

You wrote in the previous comment "replace the entire module to solve this issue. Replacing will require a visit to the dealer to re-program the cell numbers and the VIN into the pack." - (In Hungary I think the dealer can't do that. How should they do it? Do they work with OBD Peugeot software?)

Is it necessary if I change just the board? Or that have to do when change the entire module?

Thanks and sorry for the lot of stupid question. :)


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

Posted: Sun Jan 21, 2018 7:04 am
by kiev
The LTC6802 is a purpose made Lithium cell monitoring chip with analog voltage inputs and transistor drivers, but it communicates with digital data over a serial port to the big square (quad flat pack) microcontroller chip. Then the microcontroller communicates with digital data to the outside world (BMU box under the back seat) thru the CAN buss. So there is a defect somewhere between measuring the cell voltage and the reporting of that voltage to the BMU over the CAN buss.

The BMU is responsible to number the cells and modules--it sends commands which cause that identity information (the PID number) to be stored into the memory of the microcontroller of each module. This is an initialization routine that only has to be done once when the pack is built, but must be repeated if a module board (CMU) is swapped or replaced. The CMU microcontroller chip doesn't know which PID number it should respond with until it has been programmed by the BMU.

Tesla modules are on a daisy-chain serial line to a main BMS board that connects to the CAN buss. They use Texas Instrument chips that will determine module and cell numbering automatically without an external command, but for our cars we just don't know yet how it is done.

But for sure that task can be done by a dealer service department which has the Mitsubishi Universal Tester, also know as the MUT. Peugeot may have a different name, but same functioning device. The MUT communicates data and sends commands over the CAN buss to all the electronic boxes in the car. There are clones of the MUT sold on ebay, but most of them don't have the programming feature--they can only read the data and trouble codes.

It may be that the BMU is smart enough to know that a cell module board has been replaced and can re-program it automatically, but i doubt it. Also i think the VIN number of the car is also programmed into the cell module boards. So if the VIN doesn't match it will throw a trouble code and may not run. Nobody knows for sure, but you could test this theory if you wanted to swap it out and give it a try. Please share your findings and results if you do swap boards or complete modules.

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

Posted: Sun Jan 21, 2018 10:21 am
by sandange
I am no expert in this field.
I have some information from the facebook I Miev en Francaise group that may be of relevance.

Part of a posting there by Gerald Fiola– in French
Savez vous que les 4 pieces principales mcu moteurs chargeur et contrôleur communiques ensembles via une programmations Mais que la piece a un numéro unique et qu'il est pas possible de la remplacer par une autre venant d'un autre miev !!! Vraiment dommage Vous devez donc payer pour une piece neuve si vous devez changer une piece des composantes principales facture salée pour un Mcu $8000 plus installation de la folie pour l'environnement . Vraiment décevant

Google translation------

Do you know that the 4 main parts
mcu , motor, charger, and controller
communicate together via a programming But that the piece has a unique number and
it is not possible to replace it with another coming from another miev !!!
Really a pity So you have to pay for a new piece if you have to change one piece of the main components
A salted bill for a Mcu $ 8000 plus installation
All of this is craziness for the environment.
Really disappointing.
Here is a video ( in French) of an attempt to program a salvaged MCU to replace a faulty unit on a 2012 I Miev ,
Testing done at Mitsubishi with their equipment and technician the speaker in the video!

Quick rough translation is -- unable to program vin number not recognized.

------ He Now Drives a Bolt--------

More Google translated text from Gerald - not perfect but you get the general translation

So before buying the BOlt I also checked with Simon André's Auto Electrical and all the parts can be reprogrammed several times on the Volt and Bolt models.
But not on the Miev models and all those gas also from Japan ,Korea.
So the goal here is to inform you so that you are informed before buying or before changing.

I also learned that changing the 4 units together is the only way to have used replacement parts in a miev ...

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

Posted: Sun Jan 21, 2018 10:40 am
by kiev
Merci beaucoup!

We have to figure out how to re-program the VIN to re-use salvage parts--but it is a tightly coupled system that will be difficult to crack...

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

Posted: Sun Jan 21, 2018 1:27 pm
by czalbert
Or here is the hardware's way, if the software crack doesn't work. Replace the board but find the part which stored the VIN number and can communicate with the BMS and replace from the original board:

remondin Mitsubishi I-MiEVi ETACS juhtplokki eesmärgiga võtta auto originaalploki pealt maha vajalikud mikroskeemid ja panna need teise auto (Citroen C- zero) pealt kasutatuna ostetud plokile. Selgus, et ka tehase MUT3 arvutiga ei saa seda plokki teist korda üle kirjutada.

I translated with google: repairing the Mitsubishi I-MiEV ETACS control unit with the aim of removing the necessary microcircuits from the car's original block and placing them on the block purchased on the other car (Citroen C-zero). It turned out that the factory MUT3 computer can not overwrite this block for the second time.

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

Posted: Sun Feb 25, 2018 1:40 pm
by tinoale
Hi all,

I think that I may have the same issue.

My wife took the car (fully charged) for a 35km ride, no heater, arrived with one bar below 50%. She was surprised by such a poor performance but found the car with 2 more bars when she took it back home few hours later.

On the next day, when she told me that I immediately thought something was fishy. The cas was fully charged again during the night. I pulled Canion and found one cell (cell #71) was randomly droping to a lower voltage and bounding back to the normal voltage.

This video was taken with the car started in "ready" mode.
As you can see the voltage to which it drops is not always the same. It doesn't seem to stay there either, juste a blink.

I can still charge the car. But I am afraid that if a component or solder is starting to fail, this is only going to get worse until the car can't be used anymore.

My understanding from this thread is that the best bet would be to swap one (or more) of the components on the CMU board WITHOUT changing the one chip that holds the VIN configuration.

@czalbert, have you found a solution yet ? have you tried to fix the CMU board by swaping some components ?

Physically I have no idea how a "module" looks like. Could someone point me some ressource on how to dismantle the battery down to the module ? I hope I won't have to use it but I'd like to be prepared...

Thanks a lot !

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

Posted: Mon Feb 26, 2018 3:35 am
by kiev
Here's a good video on replacement of a cell


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

Posted: Mon Mar 12, 2018 9:26 am
by tinoale

My issue has repeated during several days and I noticed this :
- in the morning, my home > work trip was using as much as 10 bars of the battery gauge, which was grossly too much considering the distance. Car was cold and battery was full at the start.
- on the evening, my return trip would use only 2 bars, which is grossly too low of usage. Car was in a garage (around 10°C). And battery not full.

I deducted from this behavior that the cell voltage was only playing tricks in the morning. That could be caused by 1/ low temp and/or 2/ a full battery.

That was during a very cold week we had here. Unfortunately I could not charge at work to cross-check the behavior with a warmer but full battery at the start.

Nonetheless, the cold has passed and the gauge has stopped acting up. No more issue thus far.

So untill this happens again, I can only conclude this was due to below freezing temp. What do you think could explain this issue ?
Do I likely have a cracked solder join somewhere in this #77 cell CAN line ?
Could it be the LTC6802 that malfunction only in below breezing cold ? Does that sound like a likely failure for an electronic component ?

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

Posted: Mon Mar 12, 2018 11:37 am
by JoeS
Tinoale, glad the problem has gone away (at least, for the time being).

Very disconcerting about the dramatic loss in range - especially with the heater OFF. More confusing is the slow drop on the evening return trip. And, they average out to normal for the round trip?

From my perspective, your video did not demonstrate an unusual situation, as the the bars hop around as the car discharges and is no longer sitting at 100%SoC. I would be tempted to simply plug the car in and let it fully fully charge up and go through the balancing cycle, perhaps a couple of times.

At this point in time, there could be many sources of the problem and your speculations are but some of the ideas. I would simply continue using the car normally until it starts to repeatedly demonstrate something - for this, CaniOn is invaluable.

Sorry, I can't offer any concrete suggestions.