Sponsored

Battery Voltage Question - 11.5 Volts When Off

MidLifeCoyote

Well-Known Member
Joined
Oct 29, 2024
Threads
12
Messages
80
Reaction score
55
Location
Peoria Illinois
Vehicle(s)
2024 Mustang GT
I have a 2024 GT non PP with 17k miles. Last night I got a ford pass message that remote features were being disabled due to low battery charge. I do make short trips so as it suggested I took the long route to work this morning, about 25 minutes.

Both this morning before the drive (after the message) and this afternoon after work, my battery voltage on the dash said 11.5 volts before starting. While the engine is on, it reads 14.5 volts. I assume this means my alternator is healthy, but does 11.5 volts after about 7 to 10 hours off mean my battery isn't holding a charge well? Internet tells me battery should be around 12.5 volts when car is off, but both times at 11.5 volts the engine started fine.
Sponsored

 
OP
OP

MidLifeCoyote

Well-Known Member
Joined
Oct 29, 2024
Threads
12
Messages
80
Reaction score
55
Location
Peoria Illinois
Vehicle(s)
2024 Mustang GT
I can double check it with a multimeter tonight. Ford warranty language would seem to classify gradual capacity loss as wear and tear and thus not covered.

Anyone have experience with this?
 

GTSteve

Well-Known Member
Joined
Jan 19, 2024
Threads
1
Messages
84
Reaction score
72
Location
Tulsa
Vehicle(s)
2024 Mustang GT
I can double check it with a multimeter tonight. Ford warranty language would seem to classify gradual capacity loss as wear and tear and thus not covered.

Anyone have experience with this?
I have a 2024 GT non PP with 17k miles. Last night I got a ford pass message that remote features were being disabled due to low battery charge. I do make short trips so as it suggested I took the long route to work this morning, about 25 minutes.

Both this morning before the drive (after the message) and this afternoon after work, my battery voltage on the dash said 11.5 volts before starting. While the engine is on, it reads 14.5 volts. I assume this means my alternator is healthy, but does 11.5 volts after about 7 to 10 hours off mean my battery isn't holding a charge well? Internet tells me battery should be around 12.5 volts when car is off, but both times at 11.5 volts the engine started fine.
I have the exact issue with my '24 GT. Ended up putting a charger pigtail on the battery and connect a battery maintainer during long idle periods longer than a week. One incident last August resulted in an "update failed" message appearing, however the battery hadn't reached the low voltage threshold to trigger the "battery saver mode" alert. After trying several times to manually install the update, looked at voltage on the center display and it was at 11.5V. Updated successfully after several hours on the trickle charger. Shouldn't have to do this on a 2yo car 🙄
 
OP
OP

MidLifeCoyote

Well-Known Member
Joined
Oct 29, 2024
Threads
12
Messages
80
Reaction score
55
Location
Peoria Illinois
Vehicle(s)
2024 Mustang GT
When I checked the with multimeter last night it said 12.2V vs the dash saying 11.5V. Called dealer this morning and they said they getting lots of similar calls lately. They said it's under warranty for 3years/36K but they have to do the whole charge and test which could take most of a day, so it would need dropped off.

I'll keep a close eye on it but may have them take a look next week.
 


GTSteve

Well-Known Member
Joined
Jan 19, 2024
Threads
1
Messages
84
Reaction score
72
Location
Tulsa
Vehicle(s)
2024 Mustang GT
When I checked the with multimeter last night it said 12.2V vs the dash saying 11.5V. Called dealer this morning and they said they getting lots of similar calls lately. They said it's under warranty for 3years/36K but they have to do the whole charge and test which could take most of a day, so it would need dropped off.

I'll keep a close eye on it but may have them take a look next week.
Interesting 🤔 I may have to call service department and start a service ticket before my warranty expires. Hate having to drop it off though. Maybe I could drop the battery off? That way I won't be freaking out about possible door dings appearing!😆
 

Starship Enterprise

Well-Known Member
Joined
Jun 15, 2025
Threads
8
Messages
1,155
Reaction score
1,680
Location
MD
Vehicle(s)
2025 Mustang GT Premium
Your 2 year old car's battery health has been in slow decline from not using a Tender.

Should we have to use one? No

Do we need to? yup....
 

Zig

Well-Known Member
Joined
Jul 21, 2023
Threads
36
Messages
4,608
Reaction score
2,483
Location
Virginia
Vehicle(s)
‘24 F350 cclb drw fx4 6.7ho, ‘24 gt pp, ‘05 c6 f55, ‘01 fatboy, ‘03 sprtstr
Your 2 year old car's battery health has been in slow decline from not using a Tender.

Should we have to use one? No

Do we need to? yup....
What is the purpose of the bms?
 

Starship Enterprise

Well-Known Member
Joined
Jun 15, 2025
Threads
8
Messages
1,155
Reaction score
1,680
Location
MD
Vehicle(s)
2025 Mustang GT Premium
What is the purpose of the bms?
It's a band-aid fix to a car that has more electronic drain than the battery can handle when not being driven.

I guarantee you I'll get MUCH longer life out of this OEM battery by regularly using a tender.
 
Last edited:

AZ_Ryan

Well-Known Member
Joined
May 31, 2016
Threads
32
Messages
3,402
Reaction score
4,682
Location
Arizona
Vehicle(s)
2024 GT Premium
I have a 2024 GT non PP with 17k miles. Last night I got a ford pass message that remote features were being disabled due to low battery charge. I do make short trips so as it suggested I took the long route to work this morning, about 25 minutes.

Both this morning before the drive (after the message) and this afternoon after work, my battery voltage on the dash said 11.5 volts before starting. While the engine is on, it reads 14.5 volts. I assume this means my alternator is healthy, but does 11.5 volts after about 7 to 10 hours off mean my battery isn't holding a charge well? Internet tells me battery should be around 12.5 volts when car is off, but both times at 11.5 volts the engine started fine.
Correct. The battery isnt holding a charge and probably needs replacement. I would hook it up to a charger overnight and see what it does first.
 

AZ_Ryan

Well-Known Member
Joined
May 31, 2016
Threads
32
Messages
3,402
Reaction score
4,682
Location
Arizona
Vehicle(s)
2024 GT Premium
I can double check it with a multimeter tonight. Ford warranty language would seem to classify gradual capacity loss as wear and tear and thus not covered.

Anyone have experience with this?
I just replaced my battery under warranty for a similar issues.
 

AZ_Ryan

Well-Known Member
Joined
May 31, 2016
Threads
32
Messages
3,402
Reaction score
4,682
Location
Arizona
Vehicle(s)
2024 GT Premium
I have the exact issue with my '24 GT. Ended up putting a charger pigtail on the battery and connect a battery maintainer during long idle periods longer than a week. One incident last August resulted in an "update failed" message appearing, however the battery hadn't reached the low voltage threshold to trigger the "battery saver mode" alert. After trying several times to manually install the update, looked at voltage on the center display and it was at 11.5V. Updated successfully after several hours on the trickle charger. Shouldn't have to do this on a 2yo car 🙄
Its not the car its the batteries.
 

Starship Enterprise

Well-Known Member
Joined
Jun 15, 2025
Threads
8
Messages
1,155
Reaction score
1,680
Location
MD
Vehicle(s)
2025 Mustang GT Premium
Not true if you are daily driving the car.
Maybe...But I think that point might be debatable. The alternator never brings a battery to it's peak like a Tender does.

But TBH, This debate could only be verified one way or another by a side by side controlled experiment comparison over a period of 3-5 years....who's doing that? lol

But you drive your car daily and still needed a new battery sooner than expected didn't you?
 

AZ_Ryan

Well-Known Member
Joined
May 31, 2016
Threads
32
Messages
3,402
Reaction score
4,682
Location
Arizona
Vehicle(s)
2024 GT Premium
Maybe...But I think that point might be debatable. The alternator never brings a battery to it's peak like a Tender does.
Its not debatable. You shouldn't need to put a battery tender on a car that gets daily driven. Period.
But TBH, This debate could only be verified one way or another by a side by side controlled experiment comparison over a period of 3-5 years....who's doing that? lol
Not at all. Just use a voltmeter on a newer battery vs and old one over a few days and log the difference. Easy.
But you drive your car daily and still needed a new battery sooner than expected didn't you?
Yes. Because the batteries are garbage. As soon as I replaced mine, all my recurring problems went away. Its not a parasitic drain or the car. Its the battery. Seems like the factory batteries dont last long. There's plenty of evidence for this on the forum.
Sponsored

 
 








Top