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.
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.
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.
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.
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.
