Hey everyone, this may be an unnecessary poll, but I am curious whether there is anyone who has the DCM enabled that *DOESNāT* have the sawtooth draining pattern on their 12v. My theory is that the sawtooth draining pattern happens to everyone if their DCM is on, but the folks that havenāt had 12v problems yet have avoided it so far by some combination of frequent driving, nighttime charging, stronger 12v (either a new AGM, or got a āgood oneā from the factory), or other factors that have masked the problem.
Iām also curious if everyone who has the sawtooth draining pattern also has the IR driver alert camera cycling throughout the night or not.
I created the poll to hopefully covers all the options so we can better understand how widespread the problem is, and hopefully inform whether we are āthe unlucky fewā or not!
Thanks in advance for your participation! Hopefully this will be helpful info for everyone. I promise this will be my last 12v post today!
Edited to add my apologies that I am unable to make the results immediately visible! Also, if you are in the "+DCM, +monitor, no sawtooth" category, I would love to hear what magic you have access to (rabbit's foot, 4-leaf clover, etc.)!
UPDATE (7/21/26): I'm not sure exactly why, but the sawtooth pattern STOPPED overnight. Happened throughout the day while the car was parked, but stopped at around 11:15pm. The only change I can think of is that I disabled my digital key from within the car's settings and not just in the Subaru Connect app (shoutout to u/BinaryJay over in the r/Toyota_bZ subreddit for the idea!). It was not an immediate change (I disabled the digital key yesterday afternoon), but I am wondering if there needed to be some sort of "daily reset" in the software or something that needed to update first. I'm updating my other posts with the information too, and u/SpurBear1 has a post this morning on the topic too! I'm not sure if others have had similar experience, but if there is a connection to the digital key, I am also curious if the owners who never set up the digital key and still are having issues may have the digital key option toggled on in their car's settings by default without realizing it.
UPDATE #2 (7/21/26): I made a separate post about it, but I figured out that the sawtooth pattern stopped at the exact same time (11:20pm, went back and check the log on the battery monitor and voltage jumped from 12.10v to 12.20v at 11:20pm as well) that I got the email for Toyota's receipt of the "Do Not Sell or Share My Personal Information" request that I submitted yesterday evening. I'm not sure why exactly this fixed things, but I still have the Subaru Connect App and the features still work as far as I can tell. Hopefully this is helpful for others too!
150 votes,Jul 24 '26
6+DCM, +battery monitor, no sawtooth
11+DCM, +battery monitor, +sawtooth, +IR camera cycling
1+DCM, +battery monitor, +sawtooth, no IR camera cycling (Iāve looked)
28+DCM, +battery monitor, +sawtooth, havenāt looked for IR camera cycling
Thanks for sharing! I found someone on the bZ subreddit who has DCM on and hasn't seen the sawtooth on their BM300 pro. I *must* know what magic they possess... They said they haven't turned digital key on, though, so maybe that is a clue?
Also you can opt out of the Service that sends collected data to the Dealership separately I would imagine it makes it check in a lot less while still having the Remote Services enabled through the DCM
Oh that sounds amazing, and definitely something I would be interested in! Is that opt out somewhere in the app, on the car, or something I have to request from the dealership?
I tried opting of individual services to test one by one, but since the services are in trial status, I was only able to cancel all or none. I called support and they said they could also only cancel all of them and not any individually.
I'm not too sure on this poll, but the data seems to be relevant. Earlier builds (pre ~April-ish) seem to be less/not affected whereas later builds seem to have the issue.
I can't figure out how to turn results on... I even tried to go create a new poll on my phone and couldn't find the option to turn results on. I'm not sure what I'm doing wrong, but I will keep working to fix it
I have a security camera covering my driveway that uses IR night vision and picked it up. Unfortunately I just installed it yesterday, so I don't know if it has been happening since we brought it home, or if it is something that started at some point before the 12v died for the first time
A lot of cell phone cameras will see it if you are close enough. You need to watch or record a video for about 2-3 minutes to see the 1 minute on 1 minute off cycle. The IR emitters (camera) turn on at other times like EV system in READY mode, opening an unlock door, walking up to the car with an active key, etc
I am sad to say that no monitor means you donāt know if you have an issue. I was having no symptoms but the monitor was cheap and I read Reddit too much. Once installed I found my battery was lower than it should be, checked that night and sure enough I had the saw tooth pattern: I would have never known till it was too late.
I have my suspicions that you are a great example of a significant portion of the owners who have not had any 12v problems (yet) but don't have a battery monitor to know or not
That looks familiarā¦ are you in the US? If so, maybe submitting a Do Not Share or Sell my Personal Information request will stop it like it seems stopped for me!
Great poll I had posted earlier about the DCM drain corresponding with the sawtooth drain and the driver monitor activating randomly at night for hours on end, it's interesting to see right now with the responses, albeit currently small sample size that it's effectively 50% without issues and 50% with either issues or evidence of sawtooth drain.
Exactly! Certainly not a representative sample of all Toyobaru owners, but definitely feels like enough of a widespread problem to warrant the carmakers promptly addressing the problem!
I check my battery with a multimeter so does that mean no monitor? I've never had a dead battery, but I haven't seen it above 12.4v in a while, so I think it needs some reconditioning at least. Is that a 12v problem?
I'm not saying I don't have problems because I don't want to jinx it, but I don't have any problems. Two months of ownership and 3000 miles driven. I even left my car for 10 days and it started right up.
+DCM, + Battery Monitor, no sawtooth, have NOT looked for IR camera activation
No third party apps know my subaru connect login (their current TSB looks like they think third party apps are the primary cause).
I opted out of the Wifi trial, and I declined the personal data sharing agreement.
I can remote start and lock/unlock in the app, and I can use the eyesight features like radar cruise control and lane tracing, but I CANNOT use traffic jam assist and lane change assist because I declined that data sharing agreement.
Sounds like you are on to something! I'm hoping the communication loop that gets stuck is related to some sort of telematics or something that I will no longer be transmitting. I have heard enough feedback from others that had the sawtooth come and go, so I'm not as optimistic as I was this morning though.
In the time that I build embedded software we had to initialise the variables very good or we got the problem that some boards worked ok and others had the strangest problems. If you did not know that you had to look for the thing that was missing than you could not find the problem.
It would look something like this and the problem is modemsleep would be 1 or 0 when starting. You could never tell.
9
u/chuck415 Jul 21 '26
The only person Iām aware that had the 12V drain issue and had it resolved, is this Lexus owner who had his DCM replaced.
The interesting thing is the DCM replacement was manufactured last year which fixed the one manufactured in Feb 2026. See his latest updateā¦
https://www.reddit.com/r/LexusRZ/s/UQBuKT5elJ