Charging 12V Battery

[bmwhitetx]

I usually get all the updates to install but having issues with the RAD-PS one. Thanks to a forum member that looked up my VIN in PTS it shows failures due to 12V battery SOC. I have idled/driven truck to get to 85% SOC (per Car Scanner) and still no go. Lots of attempts. He suggests external charging and resetting BMS. I've read through a few posts but want to make sure I'm doing it right. My questions:
[EDIT: Updated with answers from following posts]

1. Can I charge the 12V battery using the jump start points under the passenger frunk cover?
YES
Or connect directly to battery terminals?
Can connect to directly to positive terminal. Cannot connect directly to negative battery terminal. Must connect downstream of BMS sensor, see below for locations.
Do I have to disconnect negative cable if charging at battery?
NO

2. I plan to buy the Clore 20A charger/power supply in case I want to go with FDRS in the future. Should I charge at 2A, 10A or 20A?
I used the Clore PL2320 charger on 10A AGM mode and it worked fine. Others have used 1A or 2A chargers with success. Note it will just take longer to get the battery to 100% so allow for that. Suggest that you buy a charger that has AGM selection for best operation. The NOCO Genius line of chargers gets good reviews on here. I liked the specs of the NOCO Genius 5.

3. I presume I do the BMS reset after the charger has charged the battery fully, right?
Do not do a BMS reset. It won't be needed if the LVB is fully charged.

If not using the jump point under the passenger frunk cover (requires twisting about 10 clips), you can easily remove the battery access panel at the back of the frunk and connect your charging clamps per this pic:

On the left the blue circle shows a lug that is downstream of the BMS sensor (the black box in front of the actual negative battery terminal). You can connect your negative clamp here. On the right, pull back the red plastic cover and connect your positive clamp to point circled in blue. Do not connect to the points with a red X. Note both these locations have a M6 stud so if you have a couple of M6 nuts you could attach ring terminals. Chargers like NOCO have clamps that can be converted to ring terminals for a more permanent hardwired connection. There is an alternate Negative/Ground location shown in the Police Modifier Bulletin. I did not check the thread size, possibly a M6 as well. Here is a pic from that:

Finally note that there are orange-colored cables that you will see when opening either the battery panel or jump-point frunk cover. These are the High Voltage DC cables that you need to stay clear of. They are insulated but don't go around probing them with sharp objects!

Also if you touch the 12V battery terminal while also in contact with the vehicle frame, you will get a tingle or buzz that may make you do something you didn't want to do. I'm just careful that I am sitting on the rubber frunk mat and not touching an exposed metal part of the frame when messing with the positive terminal and cover.

 

[chl]

All I can say is I had the same kind of issue with my 2012 Nissan Leaf when I went on a trip for multi-weeks - 12v battery went dead. All the timers and other electronics are a considerable drain.

It seems dumb, but the Li battery is not used to recharge the 12v battery except when the vehicle is on in the Leaf - seems the same with the Lightning.

My Leaf sales person didn't know that.

I had to buy an extra-long jumper cable to get the dead Leaf in my garage going again with my Ranger - the Leaf was parked nose in and regular cables would not reach.

Now I keep the Leaf 12v battery on a trickle charger/battery tender when not being driven.

Connected to the 12v battery terminals under the hood.

 

[Adventureboy]

All I can say is I had the same kind of issue with my 2012 Nissan Leaf when I went on a trip for multi-weeks - 12v battery went dead. All the timers and other electronics are a considerable drain.

It seems dumb, but the Li battery is not used to recharge the 12v battery except when the vehicle is on in the Leaf - seems the same with the Lightning.

My Leaf sales person didn't know that.

I had to buy an extra-long jumper cable to get the dead Leaf in my garage going again with my Ranger - the Leaf was parked nose in and regular cables would not reach.

Now I keep the Leaf 12v battery on a trickle charger/battery tender when not being driven.

Connected to the 12v battery terminals under the hood.

Actually the Lightning does charge the 12v from the main Lithium pack. It does this when the SOC of the 12v battery drops to 50%. It charges the 12v to 100% and then puts the truck in deep sleep mode. Unfortunately, I believe updates need > 85% and the Lightning spends much of its time in the space between 85%-50%.
Testing here: https://www.f150lightningforum.com/forum/threads/update-failed-12v-battery.16533/post-337593

 

[Mike G]

So some smart guys on the Mach-E forum recommend completely disconnecting the 12V battery to fully recharge it, and then after it's completely charged, reconnecting it and performing the BMS reset dance as you get ready to take your next drive. Here's a good read on it.

 

[The Weatherman]

I have used a trickle charger on my Lightning several times without resetting the BMS with success each time in terms of getting the updates to load.

And yes I have always used the jumper points to do so. As a matter fact I have actually modified the side fender panel to allow the trickle charger leads to remain attached and all I have to do is connect the charger and plug it in. No more pulling all this fragile turn clips.

Good luck.

 

[WRSNH]

I charged using the jump points. After charging, I checked the 12V SOC using an OBD dongle to see what the truck was seeing as the SOC. The OBD said 100% SOC, which agreed with the charger saying the charge was complete, so I did not reset the BMS. I then told the truck to apply the OTA update that had been failing, and it installed without a hitch.

 

[Bokenator]

silly follow up question, but are you using a trickle charger concurrently with plugging in to charge the Lithium ion battery? Or are you only trickle charging the 12V when the updates take place?

 

[The Weatherman]

silly follow up question, but are you using a trickle charger concurrently with plugging in to charge the Lithium ion battery? Or are you only trickle charging the 12V when the updates take place?

I have done it both ways. If the HVB is low and being charged and the LVB is also showing a low SOC, I plug in the trickle charger. If the truck doesn’t need a HVB charge and the LVB is showing a low SOC I just plug in the trickle charger.

I hate to jinx myself, but I have not had an update fail since I started monitoring the LVB.

 

[Jim Lewis]

I have used a trickle charger on my Lightning several times without resetting the BMS with success each time in terms of getting the updates to load.

What trickle charger (with any user-modifiable settings?) are you using? I just tried a Battery Tender Plus 1.25 amp trickle charger (earlier version of the following: https://www.amazon.com/Battery-Tender-021-0128-Maintain-Damaging/dp/B00068XCQU/). The Battery Tender Plus worked to charge the 12-volt battery in my Honda Accord (which wasn't AGM). The Battery Tender instructions claim it works fine for AGM batteries...

I'm charging through the jump start connectors. The tender stops charging my LVB when Car Scanner reports thru a VeePeak OBDII scanner that my LVB is only at 79% SOC. I'm running my truck now for 30-minute periods to try to jack up the LVB charge.

 

[The Weatherman]

What trickle charger (with any user-modifiable settings?) are you using? I just tried a Battery Tender Plus 1.25 amp trickle charger (earlier version of the following: https://www.amazon.com/Battery-Tender-021-0128-Maintain-Damaging/dp/B00068XCQU/). The Battery Tender Plus worked to charge the 12-volt battery in my Honda Accord (which wasn't AGM). The Battery Tender instructions claim it works fine for AGM batteries...

I'm charging through the jump start connectors. The tender stops charging my LVB when Car Scanner reports thru a VeePeak OBDII scanner that my LVB is only at 79% SOC. I'm running my truck now for 30-minute periods to try to jack up the LVB charge.

 

[The Weatherman]

What trickle charger (with any user-modifiable settings?) are you using? I just tried a Battery Tender Plus 1.25 amp trickle charger (earlier version of the following: https://www.amazon.com/Battery-Tender-021-0128-Maintain-Damaging/dp/B00068XCQU/). The Battery Tender Plus worked to charge the 12-volt battery in my Honda Accord (which wasn't AGM). The Battery Tender instructions claim it works fine for AGM batteries...

I'm charging through the jump start connectors. The tender stops charging my LVB when Car Scanner reports thru a VeePeak OBDII scanner that my LVB is only at 79% SOC. I'm running my truck now for 30-minute periods to try to jack up the LVB charge.

Here’s a link to it on Amazon.

NOCO GENIUS1, 1A Smart Car Battery Charger, 6V and 12V Automotive Charger, Battery Maintainer, Trickle Charger, Float Charger and Desulfator for Motorcycle, ATV, Lithium and Deep Cycle Batteries https://a.co/d/f0JgLNV

 

[bmwhitetx]

Success! After 47 failures since Sep 19 (many of these manual "Update now"), I got the 23-PU0110-RAD-PS update. Thanks to everyone especially @The Weatherman for their advice on using a trickle charger.

History:
I had been monitoring my 12V SOC using a BT dongle and never got above 85% but I don't drive a lot. Yesterday I took a page from @TaxmanHog and offered to help wife with errands. Lots of driving, got SOC to 93%, so tried update - and failed!

So first I charged the HVB to 90% which got the 12V SOC to 92%. Disconnected the FCSP and hooked up the battery charger and let it do its thing. When I went to bed the charger was in maintenance mode and at 1 am the scheduled update was successful. I did not do a BMS reset.

I used the Clore PL2320 in 10A mode but I think 2A would have been fine. I did connect in the battery compartment since that is an easier panel to get to and avoids the frunk clips. I was careful and connected downstream of the BMS sensor like this video shows. Do not connect to the battery's negative terminal!

Finally, this is not very convenient - having the charger hanging out the frunk while closed (I think frunk closed is a condition to get an update?) I like the idea of the NOCO chargers (1A or 2A) because they use the X-Connect system that allows you to hardwire into the vehicle with a harness and plug the charger in when needed. They even make extension cables. I would like to hear from @The Weatherman on how he does this.

 

[The Weatherman]

Success! After 47 failures since Sep 19 (many of these manual "Update now"), I got the 23-PU0110-RAD-PS update. Thanks to everyone especially @The Weatherman for their advice on using a trickle charger.

History:
I had been monitoring my 12V SOC using a BT dongle and never got above 85% but I don't drive a lot. Yesterday I took a page from @TaxmanHog and offered to help wife with errands. Lots of driving, got SOC to 93%, so tried update - and failed!

So first I charged the HVB to 90% which got the 12V SOC to 92%. Disconnected the FCSP and hooked up the battery charger and let it do its thing. When I went to bed the charger was in maintenance mode and at 1 am the scheduled update was successful. I did not do a BMS reset.

I used the Clore PL2320 in 10A mode but I think 2A would have been fine. I did connect in the battery compartment since that is an easier panel to get to and avoids the frunk clips. I was careful and connected downstream of the BMS sensor like this video shows. Do not connect to the battery's negative terminal!

Finally, this is not very convenient - having the charger hanging out the frunk while closed (I think frunk closed is a condition to get an update?) I like the idea of the NOCO chargers (1A or 2A) because they use the X-Connect system that allows you to hardwire into the vehicle with a harness and plug the charger in when needed. They even make extension cables. I would like to hear from @The Weatherman on how he does this.

I have put a series of pics together to demonstrate how I installed my trickle charger so as not have to remove the frunk side panel every time.

The main feature is the grommet I installed in the panel. It must be large enough to allow the connector pass through it. (I’m my case it was 3/4”)

After that it is just a matter of connecting the charger to this midline connector and plugging it in. (No more removing the cover.)

I keep the charger stored in the frunk so it always handy.

I
keep the charger stored in the frunk so it always handy.

 

[RickLightning]

I have put a series of pics together to demonstrate how I installed my trickle charger so as not have to remove the frunk side panel every time.

How have you connected the leads inside? The positive lead is a big post with a cover on it. Can that be removed to attach a lug and then put back on?

 

[The Weatherman]

I did not remove the under cover. I raised it, attached the charger’s clip and repositioned it as low as possible. It will not go fully back into a closed position, but it did go down low enough to reinstall the fender cover.

That red post cover can be removed, but I’m sure it can be done without the appropriate tool. Or least not without breaking it.

You may have seen that the positive post is is not actually a ‘post’. It is an anvil shaped connection piece, so to answer your question directly, I don’t think you add a lug to attach a terminated positive lead.

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