Auto stop-start suddenly staying off across restarts?

[adam1991]

Brand new '23 OBX, two weeks old now. When we first got it, ASS acted like documented--it was always on unless we turned it off after starting the car.

But it was in the shop for the last week, getting a new transfer case. (Hsit happens.) We drove it a little bit last night, turned ASS off, and I'm sure that we had ASS off when we parked it at home.

This morning I got back in and ASS was still off. ????

I drove to get bagels, got back in, and ASS was on again. Dammit. I turned it off manually.

I drove to get gas, got back in, and ASS was still off.

Any thoughts? I will continue to watch this.

My plan was to use Forscan to turn it off completely, but I'll wait a bit and watch this behavior.

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[e30rida]

hmmm.. I'm more interested in knowing why you had to replace your transfer case?

 

[adam1991]

hmmm.. I'm more interested in knowing why you had to replace your transfer case?

hehehe Faulty from the factory.

https://www.bronco6g.com/forum/threads/updated-check-4x4-warning-alert-4a.32371/post-2327697

When the car turns on 4A for you when you go to Sport mode, and it's 90 degrees and sunny, and you're in a parking lot, and you make a U-turn, and the driveline shudders as it's binding up, and you know damn well that 4A should not behave like that, and the problem goes away in 2H, and your car is three days old....yeah, you take it in to get it FIXED.

And broken it was.

My father in law has a Subaru Outback that's behaved like this since he got it, but he never bothered to get it fixed.

Anyway, back to the ASS issue: I was hoping the tech updated the software in a way that made ASS behave the way we all want it to.

 

[CarmeloS]

Nature is healing, let ASS die

 

[KANE COUNTY ILLINOIS]

Brand new '23 OBX, two weeks old now. When we first got it, ASS acted like documented--it was always on unless we turned it off after starting the car.

But it was in the shop for the last week, getting a new transfer case. (Hsit happens.) We drove it a little bit last night, turned ASS off, and I'm sure that we had ASS off when we parked it at home.

This morning I got back in and ASS was still off. ????

I drove to get bagels, got back in, and ASS was on again. Dammit. I turned it off manually.

I drove to get gas, got back in, and ASS was still off.

Any thoughts? I will continue to watch this.

My plan was to use Forscan to turn it off completely, but I'll wait a bit and watch this behavior.

Funny that you mentioned this because mine seemed to be disabled for the past month or so, but yesterday it acted up! It was nice while it lasted!

 

[Karl_in_Chicago]

Happens all the time to me but my Bronco sits for a week or more at a time . . . so battery voltage runs down a little. Once I take it for a *good* drive (not more downtown stop n' go) it works again. Just my data point.

 

[Smocaine]

ASS will stay off if your battery isn't fully recharging - you may want to have your battery health tested.

 

[buck_6G]

This issue has driven me crazy for two years, but it turns out that there are multiple conditions that must be satisfied for auto start-stop to engage:

- Battery voltage >=12v
- External temperature >32 F, <=86 F
- Vehicle speed > 3 MPH
- Driver seatbelt engaged = TRUE
- Disable Auto Start-Stop engaged = TRUE

More info on conditions governing A.S.S.

It's a shame Ford doesn't leverage the instrument cluster display to disambiguate the reasons A.S.S. isn't engaging; I'd had my dealer look at the system twice because it wasn't working when I thought it should have been.

My guess is that the external temperature conditions are set so that you don't freeze/overheat in inclement weather.

 

[adam1991]

ASS will stay off if your battery isn't fully recharging - you may want to have your battery health tested.

Brand new one day old battery straight from Ford, installed by the dealer.

Does the ASS OFF light come on in this situation?

 

[RedRider]

I'm curious about it being a "Brand new '23 OBX, two weeks old now". You posted today and I thought the 2024s have been out a while now.

 

[adam1991]

I'm curious about it being a "Brand new '23 OBX, two weeks old now". You posted today and I thought the 2024s have been out a while now.

But it is a brand new '23. 0 miles, never titled, from a Ford dealer.

Build date was December '23.

 

[RedRider]

But it is a brand new '23. 0 miles, never titled, from a Ford dealer.

Build date was December '23.

Oh gotcha, that makes more sense. Have you checked for any diagnostic trouble codes (DTCs) in Forscan?

 

[adam1991]

Oh gotcha, that makes more sense. Have you checked for any diagnostic trouble codes (DTCs) in Forscan?

Not yet. But I did hook up Forscan to see if I could just disable ASS; Forscan shows it disabled, but it is NOT disabled at all.

 

[BigMeatsBronco]

probably just a bad battery...even our 24 ranger Raptor came with a bad battery. it does happen.

 

[adam1991]

probably just a bad battery...even our 24 ranger Raptor came with a bad battery. it does happen.

As did my 23 OBX.

But I didn't know it until I took it in for what turned out to be a bad transfer case. They started their troubleshooting at the beginning, power, and discovered the bad battery. Color me impressed with the attention to detail.

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