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Comment by aftbit | Hacker News Reader

I was lucky to have the DCM in my 2019 Outback (which is responsible for cellular communication and thus this whole STARLINK thing) replaced with a bypass box under the warranty program related to the end of 3G service. My car was trying to go online 30 times an hour or something like that, draining the battery enough that it needed to be replaced after just 4 years. They don't have enough new DCMs so they were willing to replace it with a bypass box instead, which seems even better to me.

So at least my Subaru cannot connect to the cloud anymore. I'm sure it still stores location and telemetry data for insurance fraud reasons though.

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> So at least my Subaru cannot connect to the cloud anymore.

Sounds like something you can use to justify a higher selling price when the time comes

especially those that the insurers are 10x the bill on for previous driving data collection

I envy your optimism.

i've been looking at getting a used car, and this is actually one of the considerations for me. no touch screen is another.

You’d be surprised - a lot of younger dudes in particular appreciate things like this, as well as certain types of exhaust modifications and the like ;)

I had a similar issue when I connected my electricity provider to my Kia EV6. Presumably it would turn on charging when the price was optimal, but they were pinging it for status so often that the car never went to sleep, and it drained the 12V. Funny enough, the dealership couldn't figure it out; I "fixed" it by changing my Kia credentials.

FWIW i never replaced the 3g box in my 2018 subaru, and never have a battery drain issue. the battery did fail about 4 years in to owning the car, but it was a cell failure not a drain issue.

My Subaru, a 2018 outback, would be completely battery dead if I left it parked for more than a week or so. Happened once at the airport, after which I started carrying a battery pack car starter. The guy at the airport who have us a jump said it happened all the time with Subarus in long term parking.

To be fair, this happens on my 05 Outback.

This isn’t all that uncommon in any vehicle.

a week? yes it is

My local mechanic said that there is a firmware update that supposedly fixes the radio drain last time I replaced the battery but I haven't looked into it. He primarily works on Subarus and it sounded like he'd seen that as a root cause of dead battery a lot.

Is that firmware update also just replacing the 3G SIM though with a 4G one? In that case it will just fix the issue of it not being able to contact the cloud servers.

Also makes me wonder - what if someone has a subaru and lives out in a very remote area where there is no 3G or 4G service? Would that not have the same issue as the cell towers being deprecated for 3G? Seems like (specifically for Subaru owners) this might be a more common type of living situation than other car owners too!

My 2017 hasnt had the battery issue yet (they said only some subarus are supposedly affected). How did you verify how often it was trying to go online?

Now very curios in this bypass box as well - I heard just manually removing the 3G SIM (supposedly easy) can also maybe cause battery issues. If the "bypass box" alleviates all potential use of the system that is ideal long term!

That's avg time to replace a battery.

Hmm really? My Camry made it nearly 10 years, and my Civic still had a good battery 6 years in when I sold it.

Regardless, the battery and DCM were both tested by Subaru. The battery tested bad, and the DCM tested for a high parasitic draw. I drove the car daily, and the battery would die if I didn't drive it for 4 days. I didn't just make this up either, search "DCM parasitic draw" on Google for more. Subaru even sent me a letter outlining my options for repairs.

I've heard about this being a known issue with cars from other manufacturers, so I can believe it. It's interesting that nobody thought to include a way to let the vehicle know it should stop trying to communicate to handle a potential end-of-service situation like this. It's fairly common for people to keep cars for more than a decade, they're a really expensive necessity for many.

Maybe I'm used to harsher weather in the Midwest.

That's a known issue. Reports all over the subaru forums.

I tried to measure it myself with my little multimeter and now I don't have a working multimeter.

One suggestion I tried that seemed to work was to not keep the key close to the car, since that'd not physically possible for me I wrap it in an ESD bag. Haven't had much issue since, but no promises.

Lots of places will say an average car battery's life is somewhere around 3-5 years. It is highly dependent on weather. Here where there are regularly long spans of 100F+ days, a battery will have done pretty good to make it five years; many die in 3-4. Same in very cold climates. If you're in a place with good weather all the time they'll last considerably longer.

or maybe even more importantly, a garage

Depends on the battery and how it was (ab)used. I have seen batteries last only 3 years or as long as 7.

Eh, I think 6 years is kind of average. My previous one lasted 10-11 years. My current one is 8. I had two others that were 4-5 years and still going strong. This was in a location that gets reasonably hot in the summer and reasonably cold in winter. If it's only lasting you 3-4 years, then it's a shitty brand, the battery was abused, or it wasn't maintained.

my subaru is eating through batteries!

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