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

[dtbaker61]

That's odd. PID stats 483 days, but I've owned the car for 523 and neither I or the dealer replaced the battery, that I was told. However 482 days ago it was at the dealer and wen't through another master reset. So I looks like I'm going to not trust it and just buy a new one. I wouldn't think the master reset would change days in service so possibly some other thing the dealer did caused it to reset.

I think you are *pretty safe* until 36mo in service.... but be ready to replace after that for sure.

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[Stang Enthusiast]

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 contact your dealership to make sure they have a replacement on the shelf, and consider scheduling a mobile service replacement or carry it with you, along with jumper cables to make the swap yourself.

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... I pulled the cross-brace and Frunk Tub per service manual, but I think you may be able do the job just removing the cross brace and rear beauty cover

Well written write-up. Definitely, a time hog for battery replacement.

 

[azerik]

Swapped mine out due to it looking exactly like yours. I figure the Fomoco was the factory battery and if it had been replaced it’d have been Motorcraft. Wasn’t a hard swap. The new one was at 12.9 on my bench so the car is running in the garage. Thanks for the write up and reminder to do this. We’re especially hard on batteries in AZ

I replaced it anyway as there’s no way the days in service line up with reality as I would have been told if it was replaced while at the dealer(s). I was able to get it for $160 from Larry H Miller on line and picked up yesterday.

 

[MachEnthusiast]

I'm already worried about mine considering I had 12V battery faults about a month into ownership of this car. And we're nearing 36 months now.......

 

[dtbaker61]

I'm already worried about mine considering I had 12V battery faults about a month into ownership of this car. And we're nearing 36 months now.......

I'd call your dealership just to make sure they have one ready for you.... schedule a 'battery test' on a good 12v tester to see if you can get the battery replaced under warranty, and ask if they offer mobile replacement service if and when you need a replacement if the battery tests ok for now.

 

[zeta]

Has anyone found batteries from other places that are not from the dealer? I feel like some places are more convenient and a better warranty

 

[Mach-Lee]

Has anyone found batteries from other places that are not from the dealer? I feel like some places are more convenient and a better warranty

You can order the OEM replacement from RockAuto.com

 

[zvez]

Swapped mine out due to it looking exactly like yours. I figure the Fomoco was the factory battery and if it had been replaced it’d have been Motorcraft. Wasn’t a hard swap. The new one was at 12.9 on my bench so the car is running in the garage. Thanks for the write up and reminder to do this. We’re especially hard on batteries in AZ

I replaced it anyway as there’s no way the days in service line up with reality as I would have been told if it was replaced while at the dealer(s). I was able to get it for $160 from Larry H Miller on line and picked up yesterday.

so is it a straightforward swap out like regular cars or do you have to do anything special with a diag tool or such?

 

[azerik]

Straight forward like in the first post. Swap the battery, leave running to charge to 100%, then the service reset and let sit for ~6 hrs. Mine has been unplugged for almost 2 weeks, 91% soc

 

[dtbaker61]

so is it a straightforward swap out like regular cars or do you have to do anything special with a diag tool or such?

did you read the top post?

 

[zvez]

did you read the top post?

actually, as with many threads on this forum, it's nine pages long, so no I didn't read the first post, but more importantly, I failed to notice the "how to" in the thread title.

 

[awiginton]

no need to count that .... you can remove/replace the battery in less than 2 hours of actual work, leave the car 'on' the next day to charge the new battery to 100%, do the reset, and let it sit overnight.

the replacement, charge, and reset do not have to be all at the same time. the charge/reset can happen anytime 'within a few days'. All it does is reset the battery capacity number of days in service and expected capacity back to 'new'.

The dealership is changing out my 12v now. I thought I could just drive it afterwards…. I have to jump through hoops. Not very hands on exp.

 

[phidauex]

Thanks for the heads up, I'm at 39 months now and fall is around the corner. Ordered a stock replacement through FordParts.com for pickup at a local dealer.

$189 battery + $18 core - $20 FordParts promo for registering w/ ford account - $150 (30k FordPass points from HVJBC recall) + $18 tax = $56 ($38 after I swap the core). NOT TOO BAD.

If you didn't have Ford Pass points to redeem, then RockAuto appears to be the price leader at $142 + core (https://www.rockauto.com/en/moreinfo.php?pk=15222013&cc=3446918&pt=2476). However, to redeem the core you have to mail the battery back at your own shipping cost, which might exceed the $18 core charge... So call it $160 to be safe.

 

[awiginton]

12v replaced at the dealership. Took about 2 hours. They said there is nothing else I have to do. But reading the thread, it says to leave it on with no ac or lights and then reset the BCM - whatever that is. The owners manual just says to replace the 12v take to the dealership. What is correct?

 

[Mach-Lee]

12v replaced at the dealership. Took about 2 hours. They said there is nothing else I have to do. But reading the thread, it says to leave it on with no ac or lights and then reset the BCM - whatever that is. The owners manual just says to replace the 12v take to the dealership. What is correct?

The dealer is supposed to reset the BMS when they replace the battery, but in a lot of cases they fail to do that. If you don’t have a way to check, I would recommend going through those steps to reset the BMS yourself to make sure it gets done.

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