12V Battery FAQ

[James III]

Excellent job Love it! - nice post!

Can you tell me of the hole over (-) Neg is over the battery terminal itself or where the ground terminal attaches (to connect there to not mess up and confuse the BMS)

I found a couple 50 mm (2in) Caps, now just need to find a hole saw that size!

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[James III]

At this point I recommend you disconnect everything, put it in the trash, and pray you didn’t damage your car. Do not use a battery saver device with alligator clips! If the positive clip touches any metal you short out the OBD port.

This is what you should be using so it’s safe:

these OBD2? with the SAE connections are not available in the UK. My clamps are the larger fully plastic type with the teeth hidden inside.
When connected, it would take a real deliberate effort to short the clamps. But I ordered SAE connectors.,
Further, I connected a NOCO genius 1. (1A)
It has a AGM mode. It’s been connected for a day and I can see that it’s now blinking green means it kicked mode. Charging LBV from 56% to 85% Seems thats as good as it gets.
Do you suppose it’s sulfation /age or just thst (1A) isn’t enough for the H3 capacity? although I’ve not seen that HVB ever charge it more that that. I know OBD charging cannot exceed 3A. So it’s basically Motorcycle mode only for any other charger/maintainer .So to use more Amps I suppose it’s getting a CTEK to connect under the hood. Do you think that might help clear sulfation and get capacity above 85% using AGM repair mode? Battery age is 30 months. 21k miles on 21 AWD 88 kWh.

 

[Mach-Lee]

Excellent job Love it! - nice post!

Can you tell me of the hole over (-) Neg is over the battery terminal itself or where the ground terminal attaches (to connect there to not mess up and confuse the BMS)

I found a couple 50 mm (2in) Caps, now just need to find a hole saw that size!

There are drilling templates elsewhere on the forum if you search.

The NOCO takes a long time to charge because it has a goofy charge termination (I don’t recommend NOCO chargers). You will need to leave it on for 3+ days without waking up or driving the car to approach 100% charge. The NOCO status light will have to turn solid green with no other lights, which can take days.

Do NOT use recondition/repair mode on the NOCO since it overcharges the battery. Slow, long-duration charging is best.

 

[Jtbuster]

Excellent job Love it! - nice post!

Can you tell me of the hole over (-) Neg is over the battery terminal itself or where the ground terminal attaches (to connect there to not mess up and confuse the BMS)

I found a couple 50 mm (2in) Caps, now just need to find a hole saw that size!

Here is the PDF from 2022. Red circles are the terminals. Black holes are the 2 1/2 in cut holes. Use black dot for centering
Amazon reference for hole saw with speed slot. Amazon reference for 2 1/2 caps.
A) The Hillman Group 58179 2-1/2-Inch Hole Nylon Knock Out Seal, Black, 2-Pack
LENOX Tools Hole Saw, Bi-Metal, Speed Slot, Arbored, 2-1/2-Inch (1772954

 

[SoriceConsulting]

I don't drive my 2021 AWD Premium much (10k miles total since I got it in May 2021). Lately, I've been just turning off the shutdown timer, starting car, turning off lights, radio, etc., then taking key fob in the house and locking the doors with the Fordpass App (as they seemed to unlock if I just locked with fob and walked away to the no key double honk warning). I then let it sit for 6-8 hours. That seems to keep the battery at a decent level (it will go from about 60% to over 90%).

Not sure if that is a good approach. Comments / advice welcome!

 

[RobbertPatrison]

My insomniac MME has trouble going to sleep, which causes unnecessary drain of the 12V battery. Each time after locking the car the battery loses ~6% of its charge after 1 hour. Overnight the drain can be a lot more. This wears out the 12V battery prematurely.

Why did Ford's engineers not let the car go to sleep immediately after locking the car? The power drained seems an utter waste. Are others seeing a similar pattern? How many have changed the 12V battery already?

Using a clamp multimeter I measure the following sequence at the negative lead of the 12V battery:

0:00 Turn car off and lock
=== 10 Amp (120 Watt) is drawn from the 12V battery for ~4 minutes
0:04 minutes
=== 2.6 Amp (32 Watt) for 1 minute
0:05 Front USB-A and USB-C sockets turn off
=== 2.5Amp (30 Watt) for 5 minutes
0:10 Some clicking of relays, Brief 10A draw.
=== 1.5 Amp (18 Watt) for 20 minutes
0:30 Rear USB sockets and 12V cigarette adapter turn off
=== 0.5Amp (6 Watt)
0:60 The 12V battery drained ~6% = 2.5Ah

The total energy lost is (1 + 0.26 + 0.5 + 0.25 =) ~2Ah out of a 35Ah capacity, consistent with CarScanner's drop of ~6% SoC after 1 hour. Each time the car wakes up when my phone gets close the same pattern starts again. The experiments were done with Bluetooth off to avoid the PAAK trigger.

I did the same measurement with the OBD2 dongle, which showed a similar timeline but a higher power drain because of the polling on the OBD2 bus. The value I measure with the clamp multimeter matches that of the OBD2 data, so the clamp meter is trustworthy. With the dongle in and CarScanner running, the car draws 6A for 30 minutes, after which the connection to the ECU is lost, but ELM stays connected.

 

[James III]

There are drilling templates elsewhere on the forum if you search.

The NOCO takes a long time to charge because it has a goofy charge termination (I don’t recommend NOCO chargers). You will need to leave it on for 3+ days without waking up or driving the car to approach 100% charge. The NOCO status light will have to turn solid green with no other lights, which can take days.

Do NOT use recondition/repair mode on the NOCO since it overcharges the battery. Slow, long-duration charging is best.

Hi just an update to say it’s been over a week now since plugging in the Noco Genius 1 into the OBD2 without going to the car with my key or activating it. I can see the charger display through the window.. It took about three days for the charge to reach maximum 95%. checking it after updating the FordPass app and then looking at the ford.com dashboard. I see that the green light is often on pulsing, at 95%, it was steady green. But the next day I see the voltage had dropped again, and looking through the window I could see the red light was on flashing.. This is the ongoing status now with the battery normally staying between 88 to 90% The red flashing light is usually on once a day when I check it then Green pulsing. That’s stopping at about 90% with solid green.
I’m wondering if this is just due to the 30 month car /,lbv battery age & sulphating? Or just the 1A trickle charge, not really enough to keep up with the daily draw on lbv?
There’s nothing plugged in or running on the car. I have a front & rear AZDOME dash cam, that’s connected to the cigarette lighter, but that’s disconnected right now because of how long it draws power after the car is shut down. (I never wanted to trust installing the hardwiring kit that that I have for the PARKING mode.) Anyway, bottom line is I just need to be able to keep the lbv battery maintained while I’m away soon for two months. I’m leaving the HVB @ 55%.
Would you recommend trying a genius, 2 or 3 amp charger, or I just leave it on the 1A till I’m back and have LBV checked for my next service before the warranty runs out?
M-Lee your input and knowledge is really appreciated. Thank you!

 

[JSW]

Hi just an update …..
Would you recommend trying a genius, 2 or 3 amp charger, or I just leave it on the 1A till I’m back and have LBV checked for my next service before the warranty runs out?
M-Lee your input and knowledge is really appreciated. Thank you!

I would invest in a quality 3 to 5 amp charger/maintainer.

 

[mkhuffman]

Hi just an update to say it’s been over a week now since plugging in the Noco Genius 1 into the OBD2 without going to the car with my key or activating it. I can see the charger display through the window.. It took about three days for the charge to reach maximum 95%. checking it after updating the FordPass app and then looking at the ford.com dashboard. I see that the green light is often on pulsing, at 95%, it was steady green. But the next day I see the voltage had dropped again, and looking through the window I could see the red light was on flashing.. This is the ongoing status now with the battery normally staying between 88 to 90% The red flashing light is usually on once a day when I check it then Green pulsing. That’s stopping at about 90% with solid green.
I’m wondering if this is just due to the 30 month car /,lbv battery age & sulphating? Or just the 1A trickle charge, not really enough to keep up with the daily draw on lbv?
There’s nothing plugged in or running on the car. I have a front & rear AZDOME dash cam, that’s connected to the cigarette lighter, but that’s disconnected right now because of how long it draws power after the car is shut down. (I never wanted to trust installing the hardwiring kit that that I have for the PARKING mode.) Anyway, bottom line is I just need to be able to keep the lbv battery maintained while I’m away soon for two months. I’m leaving the HVB @ 55%.
Would you recommend trying a genius, 2 or 3 amp charger, or I just leave it on the 1A till I’m back and have LBV checked for my next service before the warranty runs out?
M-Lee your input and knowledge is really appreciated. Thank you!

Lee is the expert on this, but I think if your solution is maintaining the LVB at 88-90%, you are good to leave it like that during your trip. Personally I would leave the car off and let the car maintain the LVB, but that's just me.

BTW, the LVB on my car is currently at 66%. That's after driving it earlier today. I'm not worried about it. Maybe if an OTA comes across and fails to install I will do something about it. But from what I can tell, my LVB is consistently between 40 and 80%. Except for when I take it for a very long drive.

 

[James III]

Lee is the expert on this, but I think if your solution is maintaining the LVB at 88-90%, you are good to leave it like that during your trip. Personally I would leave the car off and let the car maintain the LVB, but that's just me.

BTW, the LVB on my car is currently at 66%. That's after driving it earlier today. I'm not worried about it. Maybe if an OTA comes across and fails to install I will do something about it. But from what I can tell, my LVB is consistently between 40 and 80%. Except for when I take it for a very long drive.

Tks MK!
I normally leave it on its own to fend for itself. After 2-3 weeks, the car shuts itself down. I understood at that point the HVB will no longer maintain the LBV. I never was concerned much about the LBV before. . It's only on being gone 2 months and the possibility of coming back to jump the frunk to get at it. - cheers!

 

[James III]

I would invest in a quality 3 to 5 amp charger/maintainer.

Tks, I agree but max through OBD is 3A. Hence the Novo w/ AGM mode. If I need to pull the frunk panels, might as well just disconnect the LBV as Ford recommends for longer term non-use. But I will cut the access holes. So a decent charger is in the plan.

 

[Mach-Lee]

Hi just an update to say it’s been over a week now since plugging in the Noco Genius 1 into the OBD2 without going to the car with my key or activating it. I can see the charger display through the window.. It took about three days for the charge to reach maximum 95%. checking it after updating the FordPass app and then looking at the ford.com dashboard. I see that the green light is often on pulsing, at 95%, it was steady green. But the next day I see the voltage had dropped again, and looking through the window I could see the red light was on flashing.. This is the ongoing status now with the battery normally staying between 88 to 90% The red flashing light is usually on once a day when I check it then Green pulsing. That’s stopping at about 90% with solid green.
I’m wondering if this is just due to the 30 month car /,lbv battery age & sulphating? Or just the 1A trickle charge, not really enough to keep up with the daily draw on lbv?
There’s nothing plugged in or running on the car. I have a front & rear AZDOME dash cam, that’s connected to the cigarette lighter, but that’s disconnected right now because of how long it draws power after the car is shut down. (I never wanted to trust installing the hardwiring kit that that I have for the PARKING mode.) Anyway, bottom line is I just need to be able to keep the lbv battery maintained while I’m away soon for two months. I’m leaving the HVB @ 55%.
Would you recommend trying a genius, 2 or 3 amp charger, or I just leave it on the 1A till I’m back and have LBV checked for my next service before the warranty runs out?
M-Lee your input and knowledge is really appreciated. Thank you!

You have a drain that's exceeding the ability of the charger to maintain the battery. Could be from updating the FordPass app which wakes the car up for 10 minutes and drains 5% each time.

I don't recommend NOCO chargers because they operate in a constant current mode that takes forever to top charge the battery. I don't think a bigger NOCO will necessarily help.

Above 80% is fine for storage so it's okay if it's not charged to 100%.

If you want to buy a different charger, I recommend buying a BatteryMINDer or CTEK with at least 4 amps of output and an AGM mode (connected under the hood, not through the OBD port). E.g. BatteryMINDer model 2012-AGM or CTEK model MXS 5.0

 

[Stang68]

• 3rd party apps (such as Recurrent, Optiwatt, Tronity, ev.energy, Home Assistant, Homebridge, Utility smart charging app, etc.) that access vehicle or charging data 24/7. The pings from these apps wake up the car too often. Ford has mostly cracked down on this and will lock your account if they detect misuse.

Thanks for this amazing writeup!

I've been getting the "electrical system drain - service required" message popup the past few days and the only thing that's changed is I'm now using a Chargepoint charger tied to my utility to monitor for off-peak rates.

I did not give my FordPass credentials for any of this, though. Not to my utility or Chargepoint. Is it possible the Chargepoint is pinging the car for data and that's hurting the LVB? Wouldn't make a ton of sense since the Chargepoint should know if it's charging or not without pinging the car.

My LVB state of charge is currently 66% on the Ford website.

 

[Mach-Lee]

I did not give my FordPass credentials for any of this, though. Not to my utility or Chargepoint. Is it possible the Chargepoint is pinging the car for data and that's hurting the LVB? Wouldn't make a ton of sense since the Chargepoint should know if it's charging or not without pinging the car.

Are you 100% SURE you didn't enter your Ford password anywhere? It can be confusing because the window to log in looks legitimate with a Ford logo. The EVSE cannot communicate with the car to get the battery status. It can only tell the car if the charger is available or not.

It possible if the charger keeps switching on and off the power that could maybe cause a battery drain. If you watch FordPass, what does it say when the EVSE stops the charging? "Plugged in not charging" or "Charging paused"?

Are you sure it's not the welcome lighting going off repeatedly?

For more ideas about drain causes, see the beginning of this article: Thread 'How to Recondition/Service Your 12V Battery'

 

[Stang68]

Are you 100% SURE you didn't enter your Ford password anywhere? It can be confusing because the window to log in looks legitimate with a Ford logo. The EVSE cannot communicate with the car to get the battery status. It can only tell the car if the charger is available or not.

It possible if the charger keeps switching on and off the power that could maybe cause a battery drain. If you watch FordPass, what does it say when the EVSE stops the charging? "Plugged in not charging" or "Charging paused"?

Are you sure it's not the welcome lighting going off repeatedly?

For more ideas about drain causes, see the beginning of this article: Thread 'How to Recondition/Service Your 12V Battery'

Thanks for the info.

I haven't had this message pop up until this week, after more than two years with the car. That's mainly why I'm relating it to the Chargepoint and not something like PAAK or welcome lighting.

I would say I'm 99% sure I didn't enter any Ford credentials into a third party. Chargepoint nor PSEG asked for the credentials.

I had a dashcam plugged into the 12volt and when I got this error message I unplugged it, but I figured the 12V turns off when the car is off.

Regarding "Charging paused", it would usually say "Plugged in not charging". I changed that this morning to see if it could be the solution. Now instead of the *vehicle* having the charge schedule I set it to "charge whenever plugged in" and have the Chargepoint dictate when it charges on the schedule.
Perhaps that will stop the EVSE from pinging for charging data while it's plugged in since it has more inherent information about the session.

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