Lindqvist method : DIY BMU Battery Reset

elm70 said:

MadTechNutter said:

Charging it too often so it stays more often at 4.1V is a lot worse.
It is possible that at 3.6V a lead footed driver will bring the voltage momentarily down to 2.75 but the ICE will kick in before that.

Not sure why hybrid mode is a problem, the ICE is generating electricity and keeping the voltages up. I trust Mitsubishi has that sorted properly.
But artificially 'degrading' batteries much to early as it is reported everywhere is wrong.

More about that in my next post.

Click to expand...

Charging is never above 4.1v .. and has nothing to do with SOH

About hybrid mode ... if you start a long trip, the hybrid mode will kick in at around 30% SOC, now if SOH was wrong and trip start with SOC around 100% ...
Then in automatic mode the car will run in EV mode until 30% SOC, which would equate to around 3.82v ... but since SOH is "fake" and too big .. then the hybrid mode will kick in keeping the battery below the ideal voltage ... and in a long trip it can equate to tons of charge and discharge outside the ideal voltage.

Click to expand...

I never mentioned ABOVE 4.1V.
It is common knowledge that if you keep a Li-Ion battery 10% below it's rated full charge it cycle life can increase by 50% and more.
I have experienced that with many battery setups.

Never heard of an ideal voltage.

SoC is a confusing value as you can not predict how much charge you will have because I don't know the power drain of the future.
As long as I have been driving, Hybrid mode kicks in when said power drain exceeds what the battery can deliver.
So If am driving light foot with a 1C load it should not be a problem to drive at 3.65V in EV mode but when I demand 4C the voltage will drop suddenly and the ICE kicks in. This does not harm the battery, even it it reached for a split second 2.75V.
Lithium batteries degrade when they are for a longer period of time below their 0% value and dendrites can start growing.

Anyhow you tried the method so you are obviously curious too

miles556 said:

Tried it twice on 2018 PHEV sel US model but it did not work
1st time had 12v battery off for 3.5hours
2nd time 7 hours

Will try again with 14+ hours

Click to expand...

Tried again with 12v battery unplugged for 30+ hours.
Still same results. BMU was not reset! Showing 32.5 amps as before

MadTechNutter said:

According to some website "data sheet" claims up to 5500 cycles for the LEV40 before 80% SoH.
I find that questionable.
In the 25 years(on and off) experience with Li_ion batteries at work and hobby and I have NEVER found a battery that survives 5000 cycles from 0%-100% DoD and still has 80% SoH, ... arrrgh forget it, never survived such cycle count in any way at all !

Click to expand...

We've previously had 3000 as the maximum life cycles quoted in this forum = the 10 years promised by Mitsu @ 1 complete charge/discharge per day (approx.). :ugeek:

Tried it twice with a canadian 2018 model, no success. 2.5 and 3.5h of 12V removed...

fprigge said:

Tried it twice with a canadian 2018 model, no success. 2.5 and 3.5h of 12V removed...

Click to expand...

I'm also failing so far ...

I also tried:
Simple BMU Reset (Lindqvist method without all the unnecessary parts)

1. Drain Phev battery at least a bit and disconnect 12V battery (-).
2. Connect Phev charger.
3. Connect 12V (-) battery for 3 seconds to start charger.
4. Monitor battery capacity with Phev watchdog. It should show 40 Ah if reset was successful. If it still shows old capacity, repeat steps 1-4.
5. Connect 12V AUX battery (-).
6. Remove charger, start the car and check watchdog, it should show 38 Ah.

Still it is not clear how long should I wait between 3 and 4

MadTechNutter said:

I never mentioned ABOVE 4.1V.
It is common knowledge that if you keep a Li-Ion battery 10% below it's rated full charge it cycle life can increase by 50% and more.
I have experienced that with many battery setups.

Never heard of an ideal voltage.

SoC is a confusing value as you can not predict how much charge you will have because I don't know the power drain of the future.
As long as I have been driving, Hybrid mode kicks in when said power drain exceeds what the battery can deliver.
So If am driving light foot with a 1C load it should not be a problem to drive at 3.65V in EV mode but when I demand 4C the voltage will drop suddenly and the ICE kicks in. This does not harm the battery, even it it reached for a split second 2.75V.
Lithium batteries degrade when they are for a longer period of time below their 0% value and dendrites can start growing.

Anyhow you tried the method so you are obviously curious too

Click to expand...

Yes, you are right, you did not mention anything above 4.1v

About 10% ... I'm not sure ... I was reading that ideal storage SOC for Lithium battery is between 30% and 50%

Yes, some chinese company ship Lithium battery with 10% SOC, or even less, but I believe this is because of airlines policy and risks

It Mitsubishi decided to have the hybrid charging/discharge happening at 30% ... I believe it is for a reason .. so to move this down to 10% does not look "recommended"

I'm interested to gain more SOH and extend my EV range ... but I will be monitoring the voltage of the cell and rest SOC after usage .. for then adapt my style on long drive in hybrid mode, which I might have to manually control with save and/or charge

So far I did failed on reset my BMU ... so this is possibly just a theoretical issue for me

Hi. This method works.

OK lets start from begging. PHEV MY 2014 with 110k km when purchased 2 months ago. Now I've got 113k km.
First try failed but second time I've succeeded.

What I did (and time)
2019-07-23
5:10 pm:
- disconnected 12 V batterry
~ 10:10 pm
- connected charger
- connected 12V battery for "one-two-three" but not in seconds - just counted out loud.
2019-07-24
~ 6.30 am (after ~ 8,5 hours charging)
- disconnected charger
- connected 12V battery (and tighten the screw)

After I've hoped into the car and turned it on I've got full battery charge, but with warning "EV SYSTEM SERVICE REQUIRED". I've checked PHEVWatchdog and had 105,3% of charge (40Ah) - YUPI !!! I drove for about 8 km. During that time I've check AWD system and regen all works (had PHEVWatchdog on the whole time). After stopping and switching off and on again warning was gone but when I've check PHEVWatchdog battery was at 100% so back to 38Ah.

I'll try to add video with connection/disconnecting of 12V battery.

elm70 said:

fprigge said:

Tried it twice with a canadian 2018 model, no success. 2.5 and 3.5h of 12V removed...

Click to expand...

I'm also failing so far ...

I also tried:
Simple BMU Reset (Lindqvist method without all the unnecessary parts)

1. Drain Phev battery at least a bit and disconnect 12V battery (-).
2. Connect Phev charger.
3. Connect 12V (-) battery for 3 seconds to start charger.
4. Monitor battery capacity with Phev watchdog. It should show 40 Ah if reset was successful. If it still shows old capacity, repeat steps 1-4.
5. Connect 12V AUX battery (-).
6. Remove charger, start the car and check watchdog, it should show 38 Ah.

Still it is not clear how long should I wait between 3 and 4

Click to expand...

Try counting "One-Two-Three"

michalsarna said:

Try counting "One-Two-Three"

Click to expand...

:ugeek: :ugeek:

What about get a relation with the sounds.

My car once I reconnect the 12v does a sequence of 3 or 4 click .. from the car.
Then after this there is a click from the charging box

If I stop before the charging box make a click, the charging process will not start, so definitely it is too early

So ... 12v battery need to be disconnect after the charging box make a click .. (or milliseconds before ?)

I did try to remove the 12v connection in the shortest possible time that did allow charging to start .. but I might had multiple partial restart in the middle ... since I made 2 or 3 tentative which did not cause to start charging.

I will try again .. but it is not really a reliable process ...

I was hoping the shorter method would have been effective, but it was now

I will try again in the weekend ... more or less .. I can try only once per week ... so ... I might take some time only for check other few times.

michalsarna said:

Try counting "One-Two-Three"

Click to expand...

Maybe you can try to record your 1-2-3 ... and extract from it how many seconds it did take (any decent wave editor should be able to show the length of a audio segment) ... and add to this if there was any delay between connecting and disconnecting from the wording ...

So .. maybe we can have a more "precise" time :ugeek:

elm70 said:

michalsarna said:

Try counting "One-Two-Three"

Click to expand...

Maybe you can try to record your 1-2-3 ... and extract from it how many seconds it did take (any decent wave editor should be able to show the length of a audio segment) ... and add to this if there was any delay between connecting and disconnecting from the wording ...

So .. maybe we can have a more "precise" time :ugeek:

Click to expand...

I have a recording but will have time in evening to edit it out and boost sound so we can hear clicks - hopefully.

michalsarna said:

elm70 said:

michalsarna said:

Try counting "One-Two-Three"

Click to expand...

Maybe you can try to record your 1-2-3 ... and extract from it how many seconds it did take (any decent wave editor should be able to show the length of a audio segment) ... and add to this if there was any delay between connecting and disconnecting from the wording ...

So .. maybe we can have a more "precise" time :ugeek:

Click to expand...

I have a recording but will have time in evening to edit it out and boost sound so we can hear clicks - hopefully.

Click to expand...

Did you record the successful procedure ?

In case it will be super if you post it on youTube :ugeek:

... and please post the link of your video here.

Did you hear any relay clicks after the ESVE kicked in while you were still counting?
Maybe from three relays normally required, only one or two were activated.

I am starting to think that this has nothing to do with discharging capacitors to clear volatile memory but bringing the car in an undefined state that the BMU/ECU was not programmed for.
The time the 12V was disconnected could be irrelevant.
It doesn't figure out that some try for 15 hours and it doesn't work and for others it works with only 2 hours.
Somebody reported that they shorted the rest voltage straight after they disconnected the 12V battery and it even worked without waiting.
That is rubbish, I checked that the voltage drops to below 10mV straight after I remove the 12V. Something else is going on here.

Have someone tried to connect the + cable from 12vdc battery to the ground? I know it used to reset all the information on the previous car I owned. It get’s all the stored energy from the computer discharged.

MadTechNutter said:

... and please post the link of your video here.

Did you hear any relay clicks after the ESVE kicked in while you were still counting?
Maybe from three relays normally required, only one or two were activated.

I am starting to think that this has nothing to do with discharging capacitors to clear volatile memory but bringing the car in an undefined state that the BMU/ECU was not programmed for.
The time the 12V was disconnected could be irrelevant.
It doesn't figure out that some try for 15 hours and it doesn't work and for others it works with only 2 hours.
Somebody reported that they shorted the rest voltage straight after they disconnected the 12V battery and it even worked without waiting.
That is rubbish, I checked that the voltage drops to below 10mV straight after I remove the 12V. Something else is going on here.

Click to expand...

Video of only clicking part but not altered in any way is here: https://youtu.be/DohPb9MJoSk
I've extracted sound part and will try to clean it.

In my opinion discharge step is not the most important one.
I would concentrate on connection and disconnecting 12V battery. This is most important part.
What I've noticed watching my recordings is that car was not showing that it's charging.
Only charger was indicating that there is a power going to battery.

One small question, by charging the car with the 12V battery disconnected, wouldn’t you loose all your battery protections, as well as your battery cooling fan? Be careful to slow charge in not too warm environnement.

I've annualized sound and came with that.
Unfortunately I can't add wav file, but I will record standard charging sounds without any talking so maybe we will be able to reason from there.

Carlostratos said:

One small question, by charging the car with the 12V battery disconnected, wouldn’t you loose all your battery protections, as well as your battery cooling fan? Be careful to slow charge in not too warm environnement.

Click to expand...

No

While charging there is always the DC/DC that provide 12v (normally for charge the 12v battery) from the main battery to the car 12v system line .. so no issue on this

Anyhow ... I don't get the issue on slow charge

Wow michalsarna, good job filtering out those relay clunks

I tried a few times before you send this image, trying to get it not to show any charge display but to no avail. I had to go places and had no time, couldn't even finish the charge.
I assume you mean the red plug-in symbol in the dash and the green light in park lock button, when you said the car does not show it is charging.

Tomorrow I will try synching the 12V on-time with those 4 relay clunks. I hope others try that too.

michalsarna said:

I've annualized sound and came with that.
Unfortunately I can't add wav file, but I will record standard charging sounds without any talking so maybe we will be able to reason from there.

Click to expand...

Super job michalsarna

We have both your video and the picture of audio file .. it is looking the connection/disconnet process is around 3.2 seconds

I will try to replicate this on my car in the weekend