Battery issue, Charging issue or BMS issue?

[Raptorbert]

Couple things for OP:

Are you positive start/stop is not functioning due to the battery charge? The SS strategy seems pretty complicated for it to work and may not be battery related at all and is just normal operation. If you aren't getting deep sleep mode or other issues it's probably fine. I'm pretty sure the BMS is set to not exceed 80% state of charge anyway. Tough making sense of any of the voltage readings given how complex the system is.

Knock on wood I haven't had battery issues on my early 2021. Not even a deep sleep mode notification. Completely anecdotal, some of my modules were updated at an early service and I have had zero issues with OTA updates over the last 2+ years. My truck is also parked far underground in a concrete structure away from my key fobs.

Seems like some battery problems are related to module issues (not sleeping because key fob is too close, some self test/boot loop, who knows - some guy even had a video of his fuel pump not turning off that would drain the battery after a couple hours). Or the truck getting stuck in some voltage sucking OTA update glitch. There is also a TSB that may apply related to the A/C system causing a battery drain.

I’ll be honest I’m just a hobbyist forscan mechanic and have no real idea what was going on or how to diagnose but I keep pointing to my dongar dash cam adapter that plugs into my rear view mirror harness. You can see it turn off with turning off the ignition but I haven’t had a problem with the stop start not working since removing it. I’m going to give it a week or two and then plug it in and see if the issue comes back.

 

[1BAD454SSv2]

I’ll be honest I’m just a hobbyist forscan mechanic and have no real idea what was going on or how to diagnose but I keep pointing to my dongar dash cam adapter that plugs into my rear view mirror harness. You can see it turn off with turning off the ignition but I haven’t had a problem with the stop start not working since removing it. I’m going to give it a week or two and then plug it in and see if the issue comes back.

Doesn't the dash camera still have power to it in case it gets bumped while parked ?

 

[Donmatteo]

@NJ2020 : I recently started storing my fob in a faraday box. Wonder if that may be causing an issue if the truck is always in search for a signal ? Unless I misread above and ur talking about the puddle lights always on when fob close

So do you have the walk up lighting feature enabled? I had mine on for a bit and I noticed the lights on from time to time and thought it was a glitch but realized my key was somewhat close to the truck so I turned it off. Have you noticed a difference since you started to store your key?

 

[Raptorbert]

Doesn't the dash camera still have power to it in case it gets bumped while parked ?

No the power to the usb gets cut when you turn off the vehicle. The dash cam never stays on.

 

[gdflynn1]

So do you have the walk up lighting feature enabled? I had mine on for a bit and I noticed the lights on from time to time and thought it was a glitch but realized my key was somewhat close to the truck so I turned it off. Have you noticed a difference since you started to store your key?

I do, thinking of disabling. Haven't noticed a difference since storing but I can probably correlate a close timeline of when I started storing to when the original battery saver mode messages started , or as my old Psych professor would always say in my college class: it's just coincidence

 

[taquitos]

My truck likes to do the system off to save battery thing and deep sleep when I’ve left it sitting for about three or four days. I’ve never had it not start and it never does it during a usual work week which is 20 min to work and 20 min back. I’m curious how many circuits have power when the truck is off. It feels like it’s similar to a computer getting put to sleep where it’s never actually off until it puts itself in deep sleep. Since I’ve never come back to a dead truck I view this as intended functionality since it would be stopping whatever random processes that aren’t 100% necessary before the battery dies.

 

[NJ2020]

My truck likes to do the system off to save battery thing and deep sleep when I’ve left it sitting for about three or four days. I’ve never had it not start and it never does it during a usual work week which is 20 min to work and 20 min back. I’m curious how many circuits have power when the truck is off. It feels like it’s similar to a computer getting put to sleep where it’s never actually off until it puts itself in deep sleep. Since I’ve never come back to a dead truck I view this as intended functionality since it would be stopping whatever random processes that aren’t 100% necessary before the battery dies.

Given I’ve never received the deep sleep notification even after weeks of vacation and maybe driving just once a week on short trips, I don’t think it’s normal to get that notification and sounds like there is something causing low voltage in your case.

Truck always has power, modem is constantly pinging the mothership for FordPass features. Needs to be awake to receive OTA updates, also seemingly randomly powers up modules to do self tests occasionally even after hours of shutdown.

 

[Raptorbert]

Given I’ve never received the deep sleep notification even after weeks of vacation and maybe driving just once a week on short trips, I don’t think it’s normal to get that notification and sounds like there is something causing low voltage in your case.

Truck always has power, modem is constantly pinging the mothership for FordPass features. Needs to be awake to receive OTA updates, also seemingly randomly powers up modules to do self tests occasionally even after hours of shutdown.

Ditto. I’ve had start stop not function for weeks and system off to save battery after messing around with forscan too long but I’ve never seen a deep sleep notification.

 

[NJ2020]

@NJ2020 : I recently started storing my fob in a faraday box. Wonder if that may be causing an issue if the truck is always in search for a signal ? Unless I misread above and ur talking about the puddle lights always on when fob close

I doubt it, unless the box isn’t working great. But maybe something to try and go back to before.

 

[NJ2020]

Ditto. I’ve had start stop not function for weeks and system off to save battery after ******** with forscan too long but I’ve never seen a deep sleep notification.

I would still put money that your truck / start stop is working as intended and there are no issues (unless you have some SS related soft fault code or charging code).

I’ve never watched for it but I bet my truck goes a while without start stop functioning, maybe due to extreme weather here in MN, short trips, me running all the heated seats / defrosters triggering the system to not turn on, or driving style.