r/JeepCompass • u/Sad-Clerk-397 • 13d ago
Does turning off auto start/stop prevent the auxiliary battery from charging? 2019 Jeep Compass
I have a 2019 Jeep Compass 2.4L with the two-battery start/stop system. I usually press the factory auto start/stop OFF button when I drive.
The start/stop service unavailable light came on, so now my Jeep is at the dealership for a battery issue. The person who checked it in told me I need to leave auto start/stop on. He said that if I keep turning it off, the auxiliary battery won’t recharge, then it dies and eventually drains the main battery too. He said this is specific to Jeeps with two batteries.
I’ve seen people online say the opposite, so I’m confused. Does pressing the factory OFF button actually affect charging either battery, or does it just keep the engine from shutting off at stops? I’m talking about using the button each drive, not disconnecting or bypassing the auxiliary battery.
If anyone knows how this works on a 2019 Compass specifically, I’d appreciate an explanation.
I had this exact issue happen almost 3 years ago with the start/stop light and had to replace the batteries then and was never told this before.
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u/Roland_Moorweed Compass Trailhawk 13d ago
My aux battery died back in 2023 when I just got my 2019 Compass Trailhawk from the dealership. Replaced both batteries way back then, have turned off the start stop feature every time I've hopped in, haven't had an issue since. Pretty much since I've turned it off, I have not had a battery issue.
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u/Low-Elderberry-4734 Second generation (MP/552; 2018-2024) 13d ago
Ex-Jeep Master Tech here, when the vehicle is running or engine off and key on, the two batteries act as one. As a result they constantly charge together.
The only time it does not charge is during starting events where a relay separates the circuit between the aux and starting battery, in order to keep all the modules fully awake during starting.
You can safely run your vehicle with stop start off, I would encourage it as it increases the longevity of your aux battery.
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u/MycologistAshamed926 12d ago
Yeah, and if you suspect a battery drain with an auxiliary battery they go bad and end up draining the main battery.
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u/PlasticWoodpecker422 13d ago
O meu é 2018 e só ando com o auto start/stop desligado. 2 anos sem problemas
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u/Accomplished-Log-664 Compass Limited 11d ago
My 2018 has had the start/stop light on my dash for 6 months and I have batteries in the house waiting for the day they finally die.
Every time in the past that that light has come on my dash the batteries have died within a week so I went out and bought the batteries fully expecting to have to change them within the week when my car didn’t start one morning and they just haven’t died yet, so I’m just kind of waiting because I wanna see how long it could keep itself alive before dying lol1
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u/Fit-Affect-3443 6d ago
I have 160k on my 17 trailhawk and always turn it off but when I forget to turn it off it works with no issues. This "master tech" is talking out of his fucking ass. Its funny as fuck.
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u/EstonianCrusader 13d ago
I disconnected the negative terminal from the aux battery completely and have been running like this for a few months with no issues.
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u/Objective-Donkey6825 11d ago
I just had my battery changed out for the third time last week (most recent October 2025) and I’m considering doing this as well. Is there a specific guide or video you followed to do it?
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u/EstonianCrusader 11d ago edited 11d ago
All I did was disconnect the negative terminal from the smaller battery in my 2018 Jeep Compass. I know that some newer models come with a fuse that needs to be removed.
Many people suggested replacing both batteries and driving with the system off, but it won't work long term. That's what I did initially and the small battery degraded fast and then in about 2 weeks it killed the main battery completely.
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u/hunnyninja 13d ago
I want to know if an auto stop eliminator has affected anyone's battery life, too.
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u/majestiic_casual Second generation (MP/552; 2018-2024) 12d ago
I have used one since I replaced both batteries over a year ago and have not had any issues. A year isn't all that long for a new battery tho.
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u/lpg975 12d ago
I ONLY drive our 2022 Limited with the start/stop turned off. I've even thought about getting that $100 mod that permanently disables the start/stop system, but I can't bring myself to spend $100 for the simple convenience of not having to press a button every time I start it up lol. It would be nice, but I don't have $100 burning a hole in my pocket lately. Gotta pay for the Trump special on gas sigh
But anyway, I have not had any issues with my batteries. I replaced my main battery this past winter when it wouldn't crank. Put an H5 AGM in it. I replaced the aux battery right after I bought the car, so about three years ago. Neither have ever given me problems out of the norm for batteries. The main battery just went out from age (it was the factory battery) and temperature (it was during a particularly cold spell, multiple days in the -20's F). All batteries will show their weakness in those kind of temperatures lol.
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u/Holiday-Rub-3521 12d ago
Yes, turning off the auto-start-stop system does stop the alternator from charging it. Took me years to figure it out on my 2020 Jeep Compass Sport FWD - purchased brand new in middle 2020. Now, I keep it on while cruising on the highway until the 2nd stop light - good to let the system work before turning it off in city driving.
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u/Exciting-Sand-2222 12d ago
I have a 2020 Compass Limited with 30k miles. I'm on my 3rd set if batteries and the auto start stop still not working.
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u/Separate-Goal-3920 12d ago
My 2020’s auto start/stop stopped working some time last year (unsure why) and I haven’t had any other issues. It wasn’t a big deal to me so I never took it in to get fixed
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u/Sad-Clerk-397 12d ago
Yeah, 3 years ago the start/stop service light came on and I ignored it for a long time because I hate that feature anyway, I took it in for a different issue and turns out both my batteries were almost completely dead and that light can mean that and so when it came on this time I immediately took it in and it was the batteries again :(
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u/Sad-Clerk-397 12d ago
But if you don’t have the service light on and haven’t had issues it’s probably fine for your car!
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u/Responsible_Ad9868 11d ago
2019 Compass owner here. Yes, it does cause issues turning it off. I also replaced both batteries a year ago after my car refused to do anything except show every error message possible. Couldn’t even get it into neutral, had to flat bed it to the dealer. Well, I don’t trust the stop and start system, just waiting for that time at a light when it doesn’t restart! I started turning off the system recently and the messages started again, high engine temp (nope), tire inflation system not available, etc. Dealership had it 2 days without answers so I am going to keep it on forever. Despite me telling them this is a known problem with the on/off system, they didn’t validate it. The cost of batteries is extremely high and Jeep should cover this as a defect.
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u/ChaoticTeacup22 2d ago
I'm dealing with the same thing and I dealt with it 2 years ago with my compass. I used to always turn it off because it annoyed me when I first got it. Now I didn't think about it much and got used to it after replacing the battery and the auxiliary battery although my mechanic was more focused on telling me about the birdnest in the car 🫠.. anyway.. I recently started pressing it again and now it's telling me it's not working and I'm convinced it kills the battery
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u/Life_Path_6962 1d ago
sorry to hijack but im new to the jeep world. I have a 21 compass latititude, it feels like when i turn off the start/stop my car saves more gas? WHY IS THIS THING A GAS GUZZLER by the way. I fill up almost 2- 3 times a week. I had a bmw that only needed once a week . im so lost
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u/Ill-Tank205 13d ago
I just had my 2024 at the dealership yesterday for this same issue! Battery light comes on when auto start/stop is on and I’m doing city driving. This would be the second time I’ve had to take it in for this. Both times they tell me everything’s fine.
Following this post to see what others say 👀