Journey18

Once I shut it off, wait 20 seconds then restart it the battery saver mode is not on. Unless I have the ac on then it shows up about 30 seconds after starting

It’s got 55k miles. The battery was replaced last week with the alternator at the dealership. It does not sputter at all, drives/accelerates normally. Once I park and it sits for a few minutes, battery saver mode does not come on unless I turn the AC on. The terminals in the engine bay (since the battery is up on the wheel well) read 12.71 volts with the car off, 14.3 volts with it running measured with a multimeter. The OBD2 reader says the volts is 14 with vehicle running, drops to 13.65 with the AC on max speed and coldest temp setting. It usually doesn't pop up “battery saver mode” on the first drive of the day. Sitting in the garage with it running AC on max it didn’t show “battery saver mode”. I had to drive around for 10 minutes with the AC this time for it to come on, code reader did not pop any codes, OBD2 reader said battery was at 13.77 volts. The other day I went to work and it didn’t come on, I went to lunch and drove for 30 seconds before Battery Saver Mode came on. So I’m not sure if it’s something with it being hotter outside that kicks it on or not.

2018 Dodge Journey Crossroad with 3.6l engine. Battery saver mode keeps coming on. At first (about a year ago) it was about once a week. After a couple times I replaced the battery because it was about 5 years old. It kept happening and I just dealt with it. About a month ago it started happening more often, almost every drive. I took it to a dealer and they said the battery was bad because it was after market, then test drove it and said it “started sputtering” so changed the alternator. Any time it’s come on for me it never ran any different, just kicked off the radio, so I think the dealer was just throwing parts at it. I picked it up right before closing, and it made it 2 minutes down the road before coming back on. Any ideas what it can be? I don’t trust the dealer since they didn’t fix it the first time. It seems to only come on with the AC running (I drove to work with no AC and it didn’t come on, drove home 80% of the way with no AC and no issues, I turned on the AC and within a minute battery saver mode came on). I’m thinking it might be the battery sensor on the negative terminal, but I don’t want to just keep throwing money at it.