Failing Alternators and Flickering Battery Light - Help

[surfajl77]

I’m the owner of a 2009 Yaris S that I purchased brand new in 2009. My car currently has 406K miles on it and counting.

Please note that I am not skilled at DIY repairs. The majority of my maintenance is done at a local Firestone, while more intensive work I usually leave to Toyota.

I’ve been through about 7-8 batteries over the years. I live in Phoenix and my batteries usually start failing between 16-24 months, sometimes sooner. It’s always covered under warranty, so I’ve never had to purchase a new one.

March 2019 - the OG alternator finally goes out. I was forced to replace it with an aftermarket one, as I could not afford to wait three days for Toyota to acquire a factory one since I was out of town at the time.

September 2021 - Alternator #2 fails and is replaced at Toyota with another AutoZone one due time constraints. Battery light comes on within hours. Toyota claims the alternator is bad and promptly replaces it. Alternator #3 lasts a few days until the battery light turns on again. I return to Toyota, only for them to tell me that alternator is also bad. Alternator #4 is installed and despite my concerns, there were no issues.

Well…at least for 13 months.

Oct 2022 - 13 month old battery fails and is replaced by Toyota for free. Battery light starts flickering again, only to turn off. I take it to Toyota and they run tests and says the alternator is working fine.

Battery light just started flickering again…leaving me very frustrated. From what I’ve read, it’s likely a bad voltage regulator - which will result in ANOTHER alternator.

Why would I be going through all of these alternators? What the hell is going on?