israndy
Supercharger Hunter
That is what we are trying to figure out. Perhaps we need this thread turned into a Wiki so we can keep a data sheet in the first post
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Longer term Ohmmu experiences?
- Thread starter Durzel
- Start date
mstatkus
Member
My errors always happened a day or two after a trip. I was in Canada for 4 days, and my trunk was opened as I left the house haha. But I did not get a message on my Tesla app about replacing the battery, so I don‘t know exactly when it happened. But when I got to the car I had 3 errors and 10% SoC. And both times I’ve been under the 15% SoC that Ohmmu stated.
I’ve yet to hav the issue while using the car unlike my first ohmmu which happened while I was driving and my screen even went black for a second north of Spokane WA.
I was use to having to disconnect the HV feed in order to remove the errors, but if the new reset procedure clears them thats cool.
I’d be all for pinging Elon too haha but that is a tough needle to thread. Almost need to get a few others in the community behind it. May need to spot YouTube to see who was making Ohmmu videos and run that up a flag pole.
I’ve yet to hav the issue while using the car unlike my first ohmmu which happened while I was driving and my screen even went black for a second north of Spokane WA.
I was use to having to disconnect the HV feed in order to remove the errors, but if the new reset procedure clears them thats cool.
I’d be all for pinging Elon too haha but that is a tough needle to thread. Almost need to get a few others in the community behind it. May need to spot YouTube to see who was making Ohmmu videos and run that up a flag pole.
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Elon closes on Twitter on the 28th. Ohmmu petition auto generates a Twitter post. Bottom line, it's a 12 volt battery. What difference does it make on it's chemistry or slight voltage variances. Put a voltage regulator from a 68 Ford would probably work better.
Yes and all the earlier trolling on this thread (which thankfully has disappeared or at least abated) obscures the fact that almost every other single vehicle from basically all the other auto manufacturers has no issues when you replace the 12V lead acid battery with lithium iron phosphate, largely because their float voltages and maximum charging voltages are so close within basically a tenth of a volt or so. Only Tesla has issues, and again it's worth remembering that these only started last Fall when they started monkeying with the charging routines (and we have to presume that included the insertion of a very problematic desulfation routine).
Before that it was all seamless and without drama.
mstatkus
Member
Dysan911
Member
For whatever reason that is one update that's been on my radar for a while and just refuses to hit my car. Hopefully no issues with the battery after that one
mstatkus
Member
I’m not sure on how the cadence works. I know with my battery failures or if I’m on a road trip off wifi I normally have to manually hit Software in the car to get it to check. It worked yesterday night that way. I saw others getting 2022.36.6 as I was just getting the .5.
mstatkus
Member
Dysan911
Member
So I have had a V4 and everything was going swimmingly until I installed update 2022.36.6 last night. This morning I woke up to the dreaded low voltage battery notice and the app showed only 24% charge left. I think the issue is back with this update. I am trickle charging right now in hopes that this might be only temporary.
My v4+ finally decided to tick off the Tesla LVB logic (or lack thereof). MOS Lock in. Whatever that means.
Same exact symptoms as those who posted above before. Multiple VCFront alerts and once they set, the car proceeds to drain the battery @13A, down to @6A and fluctuates between tbe two.
Without taking action, and with those VCFront alerts set, the battery will drain from full (where it was) in a matter of 4-7hrs, at most 15hrs (at a lower draw).
The only way to stop it:
More permanent and prevents the drain
(which with the codes set will continue while using the car, tanking your efficency).
a. go through the LVB replacement steps (without actually replacing the battery) to clear the codes - discharge stops and v4+ happily goes back to working untio whatever triggers the codes happens again.
Short-term bandaid to get back home or prevent same-day drain
b. when the car is NOT being used, parked for shorter or longer periods, set the discharge enable to off to prevent the drain (and make sure to put back in befote using the car).
The Ohmmu v4+ reset procedure didnt do a thing in fixing the drain or clearing the errors BTW.
Also note, any recent update is irrelevant to this issue happening or not. An ipdate dowload or post update diags can trigger it but so can prolonged use of 12V while stationary.
It can and will rear its ugly had with anything from 2021.36.x to 2022.40.x since they all contain whatever logic the LVB dev/s puy in since mid 2021.
When it triggers is just a question of time and individual car setup, accessories and use.
I did notice that when the errors set in the car, the Ohmmu app shows only one advanced page error:
MOS lock in.
I shared all this with Sean as I bet many of you did.
Same exact symptoms as those who posted above before. Multiple VCFront alerts and once they set, the car proceeds to drain the battery @13A, down to @6A and fluctuates between tbe two.
Without taking action, and with those VCFront alerts set, the battery will drain from full (where it was) in a matter of 4-7hrs, at most 15hrs (at a lower draw).
The only way to stop it:
More permanent and prevents the drain
(which with the codes set will continue while using the car, tanking your efficency).
a. go through the LVB replacement steps (without actually replacing the battery) to clear the codes - discharge stops and v4+ happily goes back to working untio whatever triggers the codes happens again.
Short-term bandaid to get back home or prevent same-day drain
b. when the car is NOT being used, parked for shorter or longer periods, set the discharge enable to off to prevent the drain (and make sure to put back in befote using the car).
The Ohmmu v4+ reset procedure didnt do a thing in fixing the drain or clearing the errors BTW.
Also note, any recent update is irrelevant to this issue happening or not. An ipdate dowload or post update diags can trigger it but so can prolonged use of 12V while stationary.
It can and will rear its ugly had with anything from 2021.36.x to 2022.40.x since they all contain whatever logic the LVB dev/s puy in since mid 2021.
When it triggers is just a question of time and individual car setup, accessories and use.
I did notice that when the errors set in the car, the Ohmmu app shows only one advanced page error:
MOS lock in.
I shared all this with Sean as I bet many of you did.
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Just for clarity, was this the reset procedure you used that didn't work? Curious what the "MOS lock in" means as well.
"To do a reset, we will eventually have a module within the app that walks owners through the process and will just have a button that says "disable" which will take care of what is needed. For now, please follow the procedure below: Thank you.
Power Cycling the Vehicle
If your vehicle demonstrates unusual behavior or a nondescript alert is present, you can try power cycling the vehicle to potentially resolve the issue.
- Shift into Park.
- On the touchscreen, touch 'Controls' > 'Safety & Security' > 'Power Off.'
- Wait for at least two minutes without interacting with the vehicle. Do not open the doors, touch the brake pedal, touch the touchscreen, etc.
- Launch the Ohmmu app to connect to the battery, ensure/charge up so state of charge is >15%
- Turn off Enable Charge and Turn off Enable Discharge.
- Wait 10 seconds and press brake pedal to ensure car does not wake up (that car is fully powered off)
- Wait 30 seconds and then Turn on Enable Charge and Turn on Enable Discharge
- After two minutes have passed, press the brake pedal to wake the vehicle.
Yup exactly that procedure we all got from Sean and posted a few pages earlier. It didnt do anything for me aside from temporarily stopping the drain AND resetting that 'MOS lock in' alert/error in the Ohmmu app.
As soon as I completed the procedure above, and woke the car, put enable charge and enable discharge back on in the ohmmu app, the car woke with the vcfront codes still set and continued to drain the battery at 9-13A.
The only thing that stopped the drain permanently and allowed Ohmmu to charge rigjt back up to 100% SoC as I drove home (40 odd miles) was the normal install/replace procedure: powerdown, pull backseat connector, disconnect negative terminal from Ohmmu, wait, reconnect negative terminal, reconnect under seat connector, power car back on. Errors cleared, suicide drain stopped. No issues with multiple stops on the way home, same basic use as on the way out. No updates, nothing special.
As soon as I completed the procedure above, and woke the car, put enable charge and enable discharge back on in the ohmmu app, the car woke with the vcfront codes still set and continued to drain the battery at 9-13A.
The only thing that stopped the drain permanently and allowed Ohmmu to charge rigjt back up to 100% SoC as I drove home (40 odd miles) was the normal install/replace procedure: powerdown, pull backseat connector, disconnect negative terminal from Ohmmu, wait, reconnect negative terminal, reconnect under seat connector, power car back on. Errors cleared, suicide drain stopped. No issues with multiple stops on the way home, same basic use as on the way out. No updates, nothing special.
I was 'lucky' in seeing the VCFronts set exactly as I was exiting the car after that 40-50 mile drive. So I saw what was happening (short of what triggered it) in real time.
a. got to car in the early morning, after a 48+ hr deep sleep, no issues, Ohmmu at 100 % SoC, car woke up and worked normal
b. drove 40-50miles with heater on/off, car audio on/off, phones wireless charging on/off, usb recording camera feeds
c. stopped, stay in cae for a few minutes
d. exited car, before I closed all the doors Tesla app alerted about VCFront errors setting.
e. opened Ohmmu app, saw the suicide discharge starting to happen, Ohmmu SoC starting to drop.
BTW for anyone that wants to test sth else, here is a new check from Sean:
Does the car turn completely off when you do the following:
In app: disable charge and disable discharge
In MCU: under safety/security select and confirm "power off"
Then wait about 30-60 seconds; don't do anything else and then press the brake pedal, does the car remain "dead" or does it wake back up at that point? (don't enable the 12V before pressing brake)
For me the car remained dead/off.
a. got to car in the early morning, after a 48+ hr deep sleep, no issues, Ohmmu at 100 % SoC, car woke up and worked normal
b. drove 40-50miles with heater on/off, car audio on/off, phones wireless charging on/off, usb recording camera feeds
c. stopped, stay in cae for a few minutes
d. exited car, before I closed all the doors Tesla app alerted about VCFront errors setting.
e. opened Ohmmu app, saw the suicide discharge starting to happen, Ohmmu SoC starting to drop.
BTW for anyone that wants to test sth else, here is a new check from Sean:
Does the car turn completely off when you do the following:
In app: disable charge and disable discharge
In MCU: under safety/security select and confirm "power off"
Then wait about 30-60 seconds; don't do anything else and then press the brake pedal, does the car remain "dead" or does it wake back up at that point? (don't enable the 12V before pressing brake)
For me the car remained dead/off.
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I have noticed when I do a battery swap and power off the car in the safety menu, it takes about 5 minutes to be fully off. I will have footwell lights on until that happens.
None at all, BAU driving around with previously installed firmware update from a good while ago. As I mentiones above, whatever triggers the errors is embedded in all post 2021.36.x firmwares so whether you are on some recent FSD beta build, 2022.28.x, 2022.36.x or 2022.40x makes no difference. Only a matter of time.
Yes. Same here, footwell, door cards and interior lights, sometimes even useful to leave the fan on 1-2 to hear it disengage, re-engage.
BTW, lmgtfy tells me MOS lock in has something to do with a MOS tube commonly found in BMS-on-a-chip or board designs.
What I really want to know though is what does seeing that alert/error in the Ohmmu app and the discharge behavior tell Sean? And rethorically - why doesnt Elon listen to us (via free'd bird or else)?
With so many used Model 3s/Ys flooding global markets, more and more will need to service these cars and swap LVBs, swap bushings, headlight/taillights, glass panels, bumper skins, interior trim pieces. Demand for out of warranty non-OE part work is bound to grow.
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AlanSubie4Life
Efficiency Obsessed Member
It is unfortunate that there are so many issues matching the Ohmmu-required profile to what the car does. Seems like a tractable problem but perhaps not?
At this point, given the failsafes Tesla has improved over time, I am just not sure I understand the value of this Ohmmu battery over a 12V A23, 10mm wrench, and a jump starter in the frunk. Other than perhaps the slight fire risk (my only worry with that solution).
At this point, given the failsafes Tesla has improved over time, I am just not sure I understand the value of this Ohmmu battery over a 12V A23, 10mm wrench, and a jump starter in the frunk. Other than perhaps the slight fire risk (my only worry with that solution).
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