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Battery Voltage Question

exm

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Hi,

Got a new DH (about 6 weeks ago). The dealer out of state claimed to have replaced the car battery before shipping the car to me. When I was playing with Forscan, the battery start throwing low voltage levels, and upon checking, the voltage dropped to 10.5v. My Noco 10 brought the battery back to 'normal' (had it connected for over 2 days).

My question is, what is normal? When I check the battery with the car not being used for 12 hours (and car off) I get about 12.26v. Both the car charger and AI says that's too low but the battery was fully charged last week. AI says the battery might be damaged. Should I go to a dealer to have the battery replaced and if so, any thoughts how to properly request this?
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Sofa King

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Dropping the voltage to 10.5 could have caused some damage... batteries don't last long when over discharged. You could see what your AI says if you don't believe me.
 
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exm

exm

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Dropping the voltage to 10.5 could have caused some damage... batteries don't last long when over discharged. You could see what your AI says if you don't believe me.
Yep, but I don't always believe AI. That's why I'm posting here for a second opinion.
 

goodlettjr

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How long did you spend on Forscan?

Had the car been sitting for a while before getting on Forscan?

I recommend driving it after you charged it back up. Take a 30 minute drive. Short cycles doesn't seem to fully charge this car and battery combo well after an event like this. The method you used to get it back to par was good though. Now for the drive.....
 
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exm

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How long did you spend on Forscan?

Had the car been sitting for a while before getting on Forscan?

I recommend driving it after you charged it back up. Take a 30 minute drive. Short cycles doesn't seem to fully charge this car and battery combo well after an event like this. The method you used to get it back to par was good though. Now for the drive.....
Maybe 1-2 hours. Didn't realize Forscan was such a battery drain.

I drove it yesterday for 20 minutes or so. Maybe I'll take it out tomorrow for a nice long drive...
 


Sig Oris

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Hi,

Got a new DH (about 6 weeks ago). The dealer out of state claimed to have replaced the car battery before shipping the car to me. When I was playing with Forscan, the battery start throwing low voltage levels, and upon checking, the voltage dropped to 10.5v. My Noco 10 brought the battery back to 'normal' (had it connected for over 2 days).

My question is, what is normal? When I check the battery with the car not being used for 12 hours (and car off) I get about 12.26v. Both the car charger and AI says that's too low but the battery was fully charged last week. AI says the battery might be damaged. Should I go to a dealer to have the battery replaced and if so, any thoughts how to properly request this?
Resign yourself you’ll need to make it easy to connect a Trickle Charger to your car

resistance is futile
 

DT-GT

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Resign yourself you’ll need to make it easy to connect a Trickle Charger to your car

resistance is futile
…and connect it when doing anything for very long with the car not running. Forscan is a good example because you have the ignition ON.
 

goodlettjr

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Maybe 1-2 hours. Didn't realize Forscan was such a battery drain.

I drove it yesterday for 20 minutes or so. Maybe I'll take it out tomorrow for a nice long drive...
Yeah. That's a good amount of time. I would say you drained the battery and not the other way around. Use your tender when doing that in the future, because time disappears when you are playing around in Forscan. Forscan itself isn't the battery drain per sey. Think rather all of the systems on, cycling, etc. Much like a desktop / laptop, they consume more power when actively processing. Then the common denominator is the batter has a smaller reserve than previous. This leads to these types of problems. You aren't really doing anything wrong in the big picture, just need to pay attention to how long you operate on battery only.
 

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Hi,

Got a new DH (about 6 weeks ago). The dealer out of state claimed to have replaced the car battery before shipping the car to me. When I was playing with Forscan, the battery start throwing low voltage levels, and upon checking, the voltage dropped to 10.5v. My Noco 10 brought the battery back to 'normal' (had it connected for over 2 days).

My question is, what is normal? When I check the battery with the car not being used for 12 hours (and car off) I get about 12.26v. Both the car charger and AI says that's too low but the battery was fully charged last week. AI says the battery might be damaged. Should I go to a dealer to have the battery replaced and if so, any thoughts how to properly request this?
Don’t forget to reset the bms
 

friscoaggie

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Don’t forget to reset the bms
See this recommended frequently; however, is that recommended when the battery is still old. For me 12/2023 DH, recently picked up a tender as I don't drive in to work 3 days a week anymore and the battery obviously was continuously getting low. So with a 2.5 yr old battery, should I do this after my NOCO charger/tender has topped it off?
 
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exm

exm

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Zig

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See this recommended frequently; however, is that recommended when the battery is still old. For me 12/2023 DH, recently picked up a tender as I don't drive in to work 3 days a week anymore and the battery obviously was continuously getting low. So with a 2.5 yr old battery, should I do this after my NOCO charger/tender has topped it off?
Is that the Forscan option to clear the codes?
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