How-To: remove and replace your 12v battery - recommended at 36 months

[Mach-Lee]

When I first got this car, that was probably the first thing I’ve always heard was the battery, the 12 V battery so this video link I found a long time ago when I first got the car and I’m not saying there was some editing, but this girl did a good job removing the standard battery Without removing the tub. I just keep this video handy you gotta wait or scroll more towards the end, to me I ain’t removing the tub!

Your words " without same foot-clamp to secure in place" is a big red light to me. I then reviewed the remove/replace video to see that the Walmart battery is not solidly mounted and can "flop around" in the vehicle. What if the car is in an accident? This is unsafe to me. What do you think? I know one thing, I would not drive around with a loose battery in any car, especially not my MachE.

Good point. In the video they used the wrong battery. Which doesn't have the proper hold down foot, so the battery is completely loose when installed. Bad. That is an improper repair, the battery always needs to be 100% tied down so it can't move, otherwise you risk a fire if it moves and touches ground.

Spend the money and get the proper H3 AGM replacement battery so it fits and works properly. No substitutions.

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[Jerrytball]

Good point. In the video they used the wrong battery. Which doesn't have the proper hold down foot, so the battery is completely loose when installed. Bad. That is an improper repair, the battery always needs to be 100% tied down so it can't move, otherwise you risk a fire if it moves and touches ground.

Spend the money and get the proper H3 AGM replacement battery so it fits and works properly. No substitutions.

To be truthful, I wasn’t even looking at the battery she was putting in. I was just looking at how it was removed and how it could be put back in the proper battery. I would never use anything that was not made for the car. I was just liking the procedure and trying to make a point you don’t need to remove that tub. I think I’ll go to bed. Been a long day. Good night.
Sidenote, I’m trying to work a deal right now to get me a silver glacier gray GT with some different wheels a 24 model and go with a lease dealers trying to figure out we’ll see. Hopefully the battery doesn’t change the 24.

 

[dhoerl]

It is really hard to tell how bad the 12v battery is in an EV... since it is not turning over a starter/motor, it is difficult to notice as it gets 'weak'. I was watching voltage as it discharged/charged daily but that doesn't measure capacity.

As little as a week ago, the old battery was reaching 100% voltage, so that is not an indicator.

I recently bought a cheap $30 battery tester, which measures CCA and resistance... and that looked 'pretty good' last week at last measurement ... however, the failure was sudden, and the post-removal measure shows CCA well below 380, and the internal resistance way high. But, it was sudden, which is why I wrote this thread to warn people to be prepared.

I have a resistive battery tester - heating element in it - wonder if that would be a good way to assess health if used monthly.

 

[dtbaker61]

I have a resistive battery tester - heating element in it - wonder if that would be a good way to assess health if used monthly.

I don't know how much of the original 35 ah capacity is 'enough' to keep things running properly... I didn't start measuring mine until near the end of it's life, so its hard to say what our best indicator will be.

I would:
- charge 12v to 100% every couple months to prevent sulfating. easy as leaving your MME 'on' overnight in the garage.

- ask dealership to test at 35months to see if they will replace it under warranty.... or ask them to be sure to stock one for your anticipated replacement.

- be prepared to instruct a tow truck driver how to pop the hood, uncover the battery, and get you charged enough to get to a dealership.... unless they have a mobile service and can replace your battery on the spot.

 

[Schmedlack]

I don't know how much of the original 35 ah capacity is 'enough' to keep things running properly... I didn't start measuring mine until near the end of it's life, so its hard to say what our best indicator will be.

I would:
- charge 12v to 100% every couple months to prevent sulfating. easy as leaving your MME 'on' overnight in the garage.

- ask dealership to test at 35months to see if they will replace it under warranty.... or ask them to be sure to stock one for your anticipated replacement.

- be prepared to instruct a tow truck driver how to pop the hood, uncover the battery, and get you charged enough to get to a dealership.... unless they have a mobile service and can replace your battery on the spot.

Hi - I want mobile service to replace my 12V battery on the spot. A quick replacement (within several hours) done at a predermined cost, would be a happy relief. Is this a business opportunity?

 

[dtbaker61]

Hi - I want mobile service to replace my 12V battery on the spot. A quick replacement (within several hours) done at a predermined cost, would be a happy relief. Is this a business opportunity?

I would hope that 'good' ford dealerships will fold this into their 'mobile services' to keep them busy and keep our vehicles out of the shop. Dealerships have all the data on how old your MME is, they can get the proper batteries, they have your contact info, and they *could* call proactively at month 36 to schedule replacement at your home or workplace.

 

[bbulkow]

I ran my original battery 39 months... tested shortly before 36 months hoping for warranty replacement, but it still tested ok. 'Great' SoH in fact... So I thought I'd charge to 100% and test monthly until it had a problem; thinking that since these little batteries are not cranking a starter they might last a lot longer than 36 mo warranty.

They don't ;(
They can fail suddenly, and without warning....

Possibly leaving you stranded somewhere if you are not prepared. I was lucky mine failed while I was at a jobsite in town and not out at one of my jobs in the booneys. I drove to the site, got out of the car, and the doors locked behind me! PAAK 'unlock' didn't work, Door pillar code bar did not 'light up', so I was stuck. Thank God I had my phone in my pocket and not locked inside the car!

Fortunately, I had several 12v batteries at home (for my solar business), and my wife was able to bring a battery, and a set of jumper cables to get me back on the road...

- used the spare 12v and the front bumper access port connections to pop the hood​

- jumpered the spare battery to the MME connection points, which was easy since I have access holes over the 12v+, 12v-, and HV disconnect. but, I ended up popping off the drivers side beauty cover so I could close the hood over the jumper cables.​

- and was able to start the car and get to my dealership, where they had a h3 35ah battery on the shelf ($211 + $16 core charge)​

I *could* have run with the spare jumpered in if a proper replacement was not available, but I'd recommend to anyone that when you battery hits 36 months, you ought to buy a replacement and carry it with you, along with jumper cables.

So, being a diehard DIYer, I thought I'd document the remove-replacement procedure in case anybody else wants to be prepared to handle it without a tow to a dealership.

=============== DIY remove-replace the 12v ===========

removal procedure starts in service manual page 1999-2001
section 414-01, if you want the factory pictures. The process is:

- remove rear and side 'beauty covers'
- remove Tub - mostly 10mm, and a screwdriver to pop access panels
- remove cross brace - 18mm
- remove/replace battery - 10mm
- reset BCM with dealer 'Scan Tool' , or, follow 'home reset procedure'
Resetting tells the computer you have a brand new battery at 100% heath.


Reset new battery ONLY after charging it to 100%.
The easiest way to charge the new 12v to 100% is:

- turn MME ON
- Turn Vehicle>Settings>auto-off = DISabled
- turn Headlights, A/c, Heat, fan OFF
- .... and leave MME on overnight
- ODB2+Carscanner, or voltmeter, should verify that battery is 100% and
resting at 'float' voltage of 13.2v by morning

THEN, you can 'reset' the BCM to the new 100% capacity by:

- turn MME 'off' once LVB has been charged to 100%
- Press the START button without pressing the brake (ACCESSORY mode)
- Flash the high beams with the stalk 5x
- Press the brake pedal 3x
- Battery icon on instrument cluster should flash 3x to indicate reset
- Turn OFF the car
- Turn OFF Fordpass and Bluetooth if you use PAAK so car-phone are not communicating
- Park the vehicle undisturbed for 6+ hours to allow the BCM to verify the battery SoC and quiescent load


and here are the pictures...

Thanks much for including the obscure steps (and the size of that strut bolt). I'll def. be calling the dealer before embarking, if the difference is really 25 bucks and they do it at my house.....

I tried to look up non-ford batteries, and a trivial search didn't find the form factor. I'm surprised a small battery like this would cost $220 at a regular parts store - unless it's rare....

Real question!

Seems like you're as surprised as I would be that the battery went from testing good to doornail dead in the matter of a week.

Any suspicions? Car generated drain? Just One Of Those Things? Your tester? All seem unlikely, but it happened, yeah? As someone who deals with batteries all day, you must have a suspicion?

 

[Schmedlack]

I would hope that 'good' ford dealerships will fold this into their 'mobile services' to keep them busy and keep our vehicles out of the shop. Dealerships have all the data on how old your MME is, they can get the proper batteries, they have your contact info, and they *could* call proactively at month 36 to schedule replacement at your home or workplace.

Nice - You have just described a good service strategy. Simplicity and professionalism will drive service sales. I hope that the dealer community picks up on this idea. Anybody listening?

 

[dtbaker61]

Thanks much for including the obscure steps (and the size of that strut bolt). I'll def. be calling the dealer before embarking, if the difference is really 25 bucks and they do it at my house.....

I tried to look up non-ford batteries, and a trivial search didn't find the form factor. I'm surprised a small battery like this would cost $220 at a regular parts store - unless it's rare....

----
it is hard to find the h3 size 35ah with a 36mo warranty.... and the right 'foot' and terminals other than the FoMoCo. Best bet is Dealership for a 'fresh' battery.

Seems like you're as surprised as I would be that the battery went from testing good to doornail dead in the matter of a week.

Any suspicions? Car generated drain? Just One Of Those Things? Your tester? All seem unlikely, but it happened, yeah? As someone who deals with batteries all day, you must have a suspicion?

just 'one of those things' combined with no really good way to know how much (remaining) capacity is needed to have it work right in the MME.

My best guess is that as the battery ages, there may be a layer or particles of lead that peel off the internal plates... and I do drive on some dirt roads, sometimes for miles, which *might* stir things up enough inside to create a conductive bridge between plates for long enough to drain the battery rapidly, or short a cell temporarily. Not likely with AGM, I've seen it in FLA.

 

[dtbaker61]

Nice - You have just described a good service strategy. Simplicity and professionalism will drive service sales. I hope that the dealer community picks up on this idea. Anybody listening?

I hope my local dealership is.... I have a good relationship with the GM and Operations Manager since my MME was the first one in town...

 

[Schmedlack]

Good point. In the video they used the wrong battery. Which doesn't have the proper hold down foot, so the battery is completely loose when installed. Bad. That is an improper repair, the battery always needs to be 100% tied down so it can't move, otherwise you risk a fire if it moves and touches ground.

Spend the money and get the proper H3 AGM replacement battery so it fits and works properly. No substitutions.

One more thing..... If you DIY, buy a BHAGM-H3 battery from your local Ford dealer. If you buy one online and it arrives damaged, you have a time consuming return fiasco on your hands. You may have to pay more, but it's worth it.

 

[dtbaker61]

One more thing..... If you DIY, buy a BHAGM-H3 battery from your local Ford dealer. If you buy one online and it arrives damaged, you have a time consuming return fiasco on your hands. You may have to pay more, but it's worth it.

and you can be relatively sure the battery is 'fresh' and not been sitting in a warehouse for too long.

so, whether you DIY, or have the Dealership do it (maybe even via mobile service!), you should buy the BHAGM-H3 battery from your local Ford dealer.

 

[DesignMatters]

Another reason AAA makes so much sense to have. Drink a beer on my driveway while they do their thing. Easy.

 

[dtbaker61]

Another reason AAA makes so much sense to have. Drink a beer on my driveway while they do their thing. Easy.

I don't think I would use AAA for this if your local Ford Dealership has a mobile service program.

 

[Space_Pony]

RockAuto has the BHAGMH3 for $143. I would think about that before paying over $200 for that little battery.

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