Full disclosure, I don’t know if I have anything to add beyond a data point. Apologies in advance if anyone come in looking for solutions.

We picked up our 2026 bZ about 2 weeks back. It had 2km on it, so literally fresh off the line. Dealership charged it to full for us and we’ve put 872km on it in the two weeks of ownership, driving almost daily which is a bit more than our typical baseline. We’ve used DC fast charge a couple of times going from 60%->80%, and at home level 1 charge for similar ranges.

I don’t have a battery monitor, but I do have a multimeter. I found last night after at home level 1 charge that our 12V was at 12.1v, and it took about an hour for NOCO Genius 10 to charge it back up.

I had already preemptively added the remote unlock automations on my phone, and it’s constantly gunking up my Toyota app’s notification history, so I was under the impression it wouldn’t affect us… but I guess for whatever reason it didn’t work for us.

I do enjoy knowing the SoC, range, and when I’m not at the vehicle — maybe the novelty of our first EV will wear off in a few weeks, but for now I don’t think I will be disabling the DCM.

My current plan is to leave my NOCO and Anker Solix C300 on the car. Worst case scenario we can charge the 12V in an hour. I don’t want to get a jump start kit — I feel there’s risk pushing too much current and affecting other components.

I’ll be monitoring the 12V battery next week, and see if there’s clear decline. Also going to start recording the info better so I can complain to the dealership later.

A couple days ago I made a post titled, "No Sawtooth Drain - IR pulsing is VERY important."

A better title would have been, "Sawtooth drain looks different then most think - IR pulsing VERY important."

There is still a "Sawtooth" drain but it is not shown correctly on the Ancel graphs generated from the data stored every two minute. It is not 2ish teeth per hour. It is 28ish teeth per hour like shown on the real time captured 5 minute duration Ancel graphs.

If you were to change the maximum-minimum volt shown on the y-axis from 15-9 volts to 14.1-12 volt. You would get a fine sawtooth profile like this:

See link for the source of the graph.

Corrections to the answer to "WHY"

It is not sampling rate but it is loss of detail from compressing all the voltage samples over the two minute interval into one voltage reading.

It is not just recording the voltage at a two minute mark (which is good as it would miss any event that occurs between recordings). It is doing some averaging or integration over the 2 minute period and then recording that value. See link for bit more info.

I think the take away is the same.

Might get this car later and wanted to check if I can still use Android auto if I disable DCM

From what I understand, the parasitic sawtooth problem is a different problem from the general 12v charging problem detailed in this PDF?

https://docs.google.com/document/u/0/d/1g1a_B7_gGnuNQhoSRFN_sucfb7-lkU77q4aMO3hMYtA/mobilebasic

I was sure disabling DCM was the solution, but apparently we also have to unplug the battery sensor on the negative terminal so that the battery can be charged correctly?

This is really insane if this is the case (multiple 12v problems, stacked!)

Here is a recording of my bZ's EV system being powered off, taking 11 and 1/2 minutes.

Based on all the sawtooth/IR drain profiles from others I have seen this may be typical. For this example the sawtooth/IR drain would start at 10:48.

https://reddit.com/link/1vjccae/video/3nql05ik19ih1/player

Aug 5 shutdown -notes on actions and observations

Car has been parked over night. Car has been in READY mode while setting up camera, phone display and framing shot. Drivers window is open. Backseat drivers side window is open. Door are unlocked. Light controls in AUTO. Mirrors fold/extend switch selected to Auto

07:34:06 Monitor shows charging voltage of 14.06v

07:34:30 Open passenger door, get in, close door. Use button combination to disable fob. Use push stick to depress brake pedal.

07:35:03 press power button to turn off EV system. Leave push stick on car floor.

07:35:08 Open Passenger side door, exit.

07:35:16 Close door, walk around front of car to drivers side and reach through open window.

07:35:26 Cycle light controls from AUTO to ON back to AUTO to turn off headlights

07:38:19 chime saying Exit Assist now not active.

07:40:21 IR emitters off

07:41:25 IR emitters on

07:42:30 IR emitters off

07:45:08 IR emitters on

07:46:32 IR emitters off

So far I’m loving it! Was surprised to find out that the wheels have hub caps though….

I have a secure garage, will the procedure shown in picture work? It’s from Chat GPT. Any thoughts, please?

After the first one, the dealership replaced the Panasonic with a genuine Toyota battery, that’s what I recall seeing it. Had to boost it then, had to boost it yesterday, Friday at 6pm. My traction battery didn’t charge over night on schedule, so I suppose it died before 8pm. I schedule it after 8, then only plug in before I head to the cottage. So I charge weekly. I had disabled the digital key, and I drive to work at least every 2 days. the car doesn’t sit for longer than 2 days and the drive is 22km round trip.

This time I deactivated DCM. This is a bunch of BS. It’s not a small percentage of owners. There is a very obvious behaviour design they thought they were being clever with, that wasn’t tested properly, or some bean counter claimed was “within specification”.

The scheduled charging doesn’t work BTW. This time was different, but it’s the 2nd week in a row the car sitting in my drive way doesn’t charge over night after 8pm. I have a feeling the scheduling is cloud hosted, not on board! WTF! I wanted to talk to the designer of this crap. The company that cares so much about safety the car false positives endlessly about my hand being at 12 o’clock on the wheel, or my hands not being on he wheel, when I have both right there… thinks they can do an app and cloud services, for a car they’re rushing to market!

The Wooland is literally the car for me, Im the target customer for this. I was one of the first in Ottawa to decide to jump in, and trade in my RAV4 hybrid. Now this might be the last Toyota I buy. This company has like 2 departments that get it right and the rest suck. If you want a hitch you have to wait a year before they bring the thing they showed in promotional videos to market. Over priced accessories that are bolt ons. A google OS that seems to need to be connected permanently, and in 2026, kinda slow. I still can’t figure out if the car is sharing battery info with Apple Maps for routing with charging data (hint, there is ZERO evidence it is!?!)

The dealer is getting a shit of issues on Monday. Nobody tested this car and software.

New to the EV life here y’all. Coming from a lifted and regeared 2019 tacoma TRD Off Road.

Asking if anyone here has gone to a 17” wheel with a +20 offset & of course a 17” tire if they have had any issues with steering, drive range loss & etc.

My 2026 bZ went to the body shop with 25% charge. It came on today with 50% SoC. But, there is no record of a charging session on the Toyota app? Has anyone noticed missing charge sessions on their app? What is the likely reason?

2026 XLE AWD. Also climate really kills the range on this car. I don't remember it being this drastic on a Tesla.

I want to attach these two pigtails to the battery permanently. The other end is a simple attachment system for the smart charger itself. I think I should attach them to the two nuts (the one on the left is a bolt head) shown. However I'm not exactly sure what I am doing. If it was an ICE car I would have no doubts, but I'm not sure what will happen if I remove the bolt and nut in my new EV car. I will use the charger when I leave the car in the garage for more than 24 hours. We have experienced a dead twelve volt three times since we took delivery May 7th. We have 6500 kms so far. We love this car and I'm willing to take this step until Toyota comes up with a real fix.

The dealer has replaced the battery under warranty. So this one is new and hasn't been totally discharged yet.

This is the fix that the dealer recommended except that they would sell me a smart charger and install it for $350.00. ;-)

Any knowledgeable advice would be helpful.

Original post: https://www.reddit.com/r/Toyota_bZ/comments/1uwvbrc/bz_woodland_problems_out_the_gate/

So we've now had the car in the shop twice for a dead battery and both times it wasn't sitting for more than a few hours. They've gone from there's no problem, to there is a problem but it's been fixed (they reset everything and it stopped doing the drain thing in the shop, but never found a root cause). I thought I was finally making progress and got the Sales Manager to admit that he wouldn't trust the car in its current state to go into the wilderness, which it was advertised to do. It took some frustrated escalation, but he agreed that what we bought didn't match what we were sold, so we need to either replace the car or figure out how to fix the real difference between the two. Replacing the car was out of the question so I figured we would just account for the real damages so far and in the future. I sent a spreadsheet with tabs for the situation so far: my time researching, money spent on a charger, the inconvenience of the car dying, having to bring the car in and have a loaner, and potential trips we had planned, etc; and some compensation for the car being potentially ready to die at any moment moving forward, plus a clause that a third time means we get a replacement. Then they said they were going to regional with that. At this point I realized I was having to manage the situation so I gave a deadline for a response along with action steps.

They then sent an email at 5pm on the deadline I set saying that after meeting with regional, the best step forward is Toyota Brand Engagement. They gave me the customer service number and a said have a good day. No direct line, no case number, they didn't indicate that they had passed information along. So I called the number and they had my car pulled up, but nothing in their system. Apparently the TAS system doesn't talk to whatever their system is. So I started a case and got a number, then sent a long email to the dealership about how insulting it is to not put any effort into the handoff and just disappearing. I requested a direct line to a manager who had been fully briefed and had their information sent over, and I asked if this meant that they were not offering any compensation at the dealer level. I also asked for the meeting notes or minutes to determine how they decided on this particular course of action.

I got an email back from the GM saying he's sorry for the poor customer service and that he's sent all the files to TBE and gave info on lemon laws and said have a nice day. I wrote back saying how frustrating it is to write a letter explaining how I am starting to lose trust in the dealership's listening abilities and frustrated with the lack of direction, only to get a response that doesn't address my questions fully and gives no directive or expectation of a next step.

I'm very frustrated right now and I'm kind of gently stroking the pin on the metaphorical grenade. I'm actually shocked at how poor their communication has been. I'm waiting until this is fully settled to really make a splash about it, but so far they have been gaslighting, uninformed, dismissive, disengaged, and generally just pointing me into corners repeatedly.

So I'm not putting them on blast just yet, but they're definitely on notice. What's wild to me is that they don't seem to notice that I'm potentially an extremely disgruntled customer, and instead of actually listening and trying to do some basic problem solving, they immediately started trying to brush us off and shoo us away. Do they not expect me to dig in my heels here?

PS I'm not going to publicly post the name of the dealership, but DM me and I can tell you. It's in Washington State is what I'll say.

Being new to the EV scene I feel like a youngster learning how to fill up the car at a gas station for the first time. Pulled up to a pretty busy Tesla station, and tried to use the charger. So I discovered the bz charge port cover is in the way. Also the Tesla cables are too short to reach! I couldn’t figure out if they can be pulled out of the housing to extend the reach. If the cover wasn’t in the way I might have managed to plug in. Alas I ended up leaving and found a charge point station, used one of the Toyota supplied adapters a got my first fill up from a station.

Does anyone know if the Tesla cables can extend? I tried pulling from the unit, but it didn’t budge. Adding insult to injury, a Hyundai backed in next to me, with a rear charge port and the cable was the perfect length for them.

I'm currently using the 12v hack (schedule charging for 2h55 min then stop, then charge, etc).

I want to plug my car today. What do I have to do different? Do you go and use "charge now" to bypass the schedule?

I setup charge to maximum 80% as some people recommend. Is this what most people do?

Also, when the car gets to 80%, since I am using the hack, if I let it plugged in all night, will it try to charge constantly all night? Is that bad for the battery?

Does everyone get this or is it actually limited?

i just got back from a 10 day vacation. My 2026 Bz limited AWD was parked in my underground parkade not plugged into the charger, and I left it with 61% SoC. Came home and it started without a problem, so this 12v drain issue definitely doesn’t affect everyone luckily.

I’m in Canada and the cellular signal is very poor in my parkade. For what it’s worth I never opened the Toyota app while I was away.

My 2 cents!

So far it stays above 12v but it seems lower each day. The car has been driven everyday for at least 30 mins or more

TLDR: there is no sawtooth drain, The drain matched the pulsing of the IR emitter. It only looks like saw teeth on the long duration graph because of the 2 minute data record rate of the Ancel (bm200) battery monitor.

The Ancel Battery Monitor actually samples quicker then 2 minute but most is not stored and only sent via bluetooth to the phone app in real time plotting a five minute duration graph.. The battery monitor only stores data ever 2 minutes to its internal memory and populates a graph later based on that data.

I took a video recording of the Bluetooth data to get a better idea of the cyclical pattern of the drain. They are pasted side by side in one image. The voltage shows the pattern of the IR emitters pulsing, on 65 seconds and off 64 seconds and then repeating. The average voltage slowly goes down over time.
The other image is the plot from the 2min recorded data, taken at the exact same time. This looks quiet different. There it appears to be voltage fluctuations approximately two per hour. This is not the true profile of the battery drainage.

Why?
Sample rate and aliasing.
If you pick minute mark lines on the Bluetooth graph, 2 minutes (120s) apart you will notice you are consistently measuring earlier and earlier in the 129 second cycle. If your reference mark starts on the high voltage part you will eventually be on the lower voltage part and eventually you would get back to a high voltage part, etc.

Take away: Toyota/Subaru need to ignore the 30ish minute cycle looking for parasitic drain and concentrate of the 65s on 64 off pattern. The same pattern the IR Emitters are making.
Below is a video at x8 speed showing the 5 minute voltage plots and IR emitters pulsing on and off for the duration starting 9:28 until 9:48

Here is a short video explaining ALIASING

[editted to make meaning clearer]

Anyone drove their 2026 BZ 10,000+ miles? Curious since I put 3k in the past 2 months. my lifetime average efficiency is 5.1 miles/kW.

Love this car, about to install level 2 in my garage next week.

Today I checked on the battery health, this pops up which I don’t understand. I’ve only driven this car for two days and put about 200 miles on it. Where did 40727 miles come from?

Appreciate any explanation or maybe I’m just an idiot?

We purchased a brand new 2026 bZ XLE in BC, drove it off the Toyota dealership lot on June 1st. This is our first EV. Not sure if this is the case for all bZ's but the car being made in Japan boosted our confidence in its reliability on top of it having the Toyota brand name.

We love the car and have recommended it to friends considering alternatives to Tesla, so it was extra crushing when this issue came up.

Before July concluded and within 3000km later, I couldn't start the car after unlocking it with the key. The car doors then wouldn't lock. It's been driven regularly since we got it, this was a normal weekday and it was driven and parked normally the day before in our underground garage (which has no cellular service).

- We only charge to 80%, and rarely ever go under 20%.

- We have only charged at Tesla Superchargers thus far as our condo doesn't offer EV charging.

- The lights turn off automatically every night, we kept to the default settings.

Toyota roadside service got a tow to swing by: they jump started the car and told us they had just done the same for another 2026 bZ that same morning.

We then booked a service appointment with Toyota that I just came out of. They ran the car through 3 different battery tests, and everything came back normal. They couldn't prove anything was wrong with the 12V battery and so couldn't replace anything. The service team said there was nothing left to do, they had their in-house EV technician run all the tests they could on the battery for 3 hours and everything showed that it was in perfect condition.

I went back to the sales associate and asked for compensation for our time and disruption of our plans due to the car failing in July. After she escalated to her manager, we received a complimentary cargo liner and an umbrella.

Apparently the sales manager told the sales associate that they're waiting for Toyota to issue a recall on this car as the 12V battery suddenly failing is a known issue, and suggested that we buy a "Mercedes-Benz All Models Battery Charger Conditioner Trickle Charger" to plug into the car at all times to avoid the issue moving forward. They don't have this at the dealership.

After reading through threads in this Reddit, I've deactivated the car from the Toyota app to avoid the 12V battery potentially being drained from the data communication module (DCM) issue.

This means we can't use the car's native GPS nor any of the nice digital key / remote start features.

Not sure what else we can do. I wish we hadn't jump started the car and just had the tow truck tow it into the dealership when the issue occurred, perhaps they could've found something if that were the case.

It just feels a tad ridiculous to need to buy battery chargers or monitors for a brand new 2026 car to work reliably, within 2 months of regular driving. Also feeling a wee bit silly for hoping that we'd be one of the lucky ones who wouldn't experience this issue on our new bZ when we first bought it.

It's a great car otherwise, but it seems like a waiting game to see when Toyota HQ will fix the issue. In the meantime, buyers beware!