I would reinstall at a lower voltage reading and let the car bring it up to an acceptable value. Every time a battery is installed the car goes into a 6 hour charge cycle anyway. So far no messages with mine but that was the approach I tried. I could have trickle charged to 14.5 or so but left it at 14.1 to install.
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Longer term Ohmmu experiences?
- Thread starter Durzel
- Start date
mstatkus
Member
...now that I got my shim back haha! Yeah I'll tinker with that, was hoping I could squeeze in a soft update first. When I reconnected to the battery now its actually registering 99% so I'll put something on it to bring it down even though it was telling me 87% this AM.
Well, I got those same 3 errors tonight. Car has been sitting for about 3 1/2 days plugged in. I would check the 12 volt charge level using my monitor and it was constant at about 13.3 volts with an occasional spike to 14.4 for a wake up. I got a warning from the Tesla APP in my iPhone notifications to "Replace 12 volt battery soon". (At least the app now warns you if away from the car).
Reinstalled my DiehardEV battery warnings cleared. 6 hour charge cycle started normally. I will post graphs below:
Here is the charging monitor graphs the day prior and to point of failure:
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Out of the blue I just got the dreaded VC front service code. The car had been parked for 5 days. I'm not at home so my wife had to download the app and it showed 13% on the battery. Put it on a trickle charger to keep it from bottoming out. Will reach out of course to Ohmmu but this is most discouraging. More later.
Dysan911
Member
Mine as well. v4+, LiFePO4-trickled prior to install. Few weeks (maybe 6?) since install now, including two prolonged deep sleep unplugged stretches of 5+ days and one update 2022.28.2 to 2022.36.2
later and nothing... yet... for now.
Let's see what happens when 2022.36.5 is finally pushed to my old/legacy Model 3 and the car goes through the Tesla Dev OCD diagnostics procs of every sub-system and config vs hardware found.
State this morning after 8+hrs deep sleep:
later and nothing... yet... for now.
Let's see what happens when 2022.36.5 is finally pushed to my old/legacy Model 3 and the car goes through the Tesla Dev OCD diagnostics procs of every sub-system and config vs hardware found.
State this morning after 8+hrs deep sleep:
Attachments
mstatkus
Member
I think the prior comment about an over voltage may be on to something. It’s so random.
The highest voltage I ever observed was 14.5. The battery case shows a li it of 14.7. Without internal data it's hard to say like did the battery overt temp for a moment and interrupt charging (a battery BMSO) function. It's just not clear or obvious. I see the website lithiumMoto.com also had an issue with their battery and just did a redesign and is testing. All if these Lithium battery makers should get together a match data or collectively go to Tesla for a longer term solution.
This. I drive a lot. 2019 with 87k miles on it. I was concerned about battery failure so I just initiated a Tesla battery install. It was around 100 dollars and honestly. I’ll do this as a maintenance item every 3 years or 80k miles which ever comes first.
mstatkus
Member
A software update that renders a aftermarket add-on or replacement void; does indeed reduce confidence.
The MCU and GUI teams don't know what they are doing and haven't for a while... the shortsighted OE config ringfence VCFront and LVB diagnostic procs are just one example (see v11 fiasco, SoCal centric 'engineering', 12V and 15V OE LVB issues, Atom MCU planned obsolesence slowness with the move to the Ryzen config, general firmware update bloat, nav update bloat, limited use of LTE for anything but data streaming).
That's what happens when all the dev is done on simulators instead of real hardware (that has to be lived with day in and day out). Nothing new.
That's what happens when all the dev is done on simulators instead of real hardware (that has to be lived with day in and day out). Nothing new.
Waiting on Sean to decipher the practical meaning of and use of 'disable charging' and 'disable discharging' in the app.
One thing Ive been doing, which is either OCD overkill or useful somehow is: after using the Ohmmu app and before closing it (which actually seems to work correctly on Android and kills the process), I disconnect the app/phone bluetooth handshake to the Ohmmu battery.
One thing Ive been doing, which is either OCD overkill or useful somehow is: after using the Ohmmu app and before closing it (which actually seems to work correctly on Android and kills the process), I disconnect the app/phone bluetooth handshake to the Ohmmu battery.
Trial and error. Mostly errors. Why is charging and maintaining a 12 volt battery so difficult?
I received a note from Ohmmu on using the app to reset and clear alerts. I will copy here as I have a V4 not V4+ so doesn't apply to me.
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.
I posted how to use the app to reset. Those instructions will become part of an app update.
After getting back from the West Coast was able to do a little more research on the appearance of the dreaded FC front 12-volt system code after a month of smooth sailing and encountered something I cannot explain. I was planning on just charging up the battery and then driving around for today and then doing the reset later this afternoon. However, after charging the battery up (had to disconnect it since the charger only puts out ~50 watts and the car draws 40W when not in deep sleep) monitoring the battery via the app suggested either just stupidity or a malicious programming effort on Tesla's part - or perhaps some hidden draw that I can't understand. Or perhaps some combination of stupidity and malice. As somebody once said, it's typically better to explain bad behavior with incompetence than with resorting to character assassination but this is really a tough contingency to explain. From the standpoint of reasonable design, it makes no sense whatsoever.
The car was discharging the 100% battery at a rate of more than 16 amps, and would have resulted in a dead battery according to the app in two or three hours. I have no idea why the 12 volt system would draw that kind of current since there was no in cabin heat being called for. Seems astonishingly stupid (if not just some kind of deliberate effort to get the battery to fail more quickly) to draw 16 amps from a battery that the system designates as defective and not charging properly. Bizarre. Obviously this is how people get stranded on very short notice. Collectively it seems as though owners are not in a position to influence Tesla very much but this is just plain unf------ acceptable. Will also send a copy of this to Ohmmu.
Any insights?
The car was discharging the 100% battery at a rate of more than 16 amps, and would have resulted in a dead battery according to the app in two or three hours. I have no idea why the 12 volt system would draw that kind of current since there was no in cabin heat being called for. Seems astonishingly stupid (if not just some kind of deliberate effort to get the battery to fail more quickly) to draw 16 amps from a battery that the system designates as defective and not charging properly. Bizarre. Obviously this is how people get stranded on very short notice. Collectively it seems as though owners are not in a position to influence Tesla very much but this is just plain unf------ acceptable. Will also send a copy of this to Ohmmu.
Any insights?
Instructions above on how to do a reset via the app and clear the warnings. I haven't tried it as I still have a V4 with the (+) coming in a month. Very odd why a 16 amp draw while parked with major draw items off. It's like the system spots a battery it doesn't like and tries to drag it down to failure to set off a warning. Like you, my V4 was working very normal for almost 4 days then all of a sudden the lockout occurs and it starts to drag down. I spotted it in short order and intervened before a dead battery. Now, it I had the V4+ and I got the change battery warning from the Tesla app, I could (I guess within bluetooth range) reset. Not sure how long that would last. At this point, ALL the lithium manufacturers should corner Tesla for a working solution since more than just Ohmmu is now affected.
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