psyclone
Posts: 8
Joined: Thu Apr 22, 2021 9:36 am

Re: Dead 12V battery then traction control freaks out

Sat Jul 03, 2021 5:31 pm

OMG...@triangles You have been a ton of help in preparing me for what I'm afraid I'm facing. I see your last post was almost 2 years ago. IF you're still on this forum, did it work? AND, if it did work, where are those pics to run the low voltage disconnect. You quite possibly have saved me a LOT of money and the car from the junk yard. Thanks

Anti_Climax
Posts: 117
Joined: Fri May 20, 2016 12:22 pm
Location: The Valley of the Sun

Re: Dead 12V battery then traction control freaks out

Tue Jul 06, 2021 10:55 am

Triangles is around. Shoot a DM if nothing else.
2012 Candy Blue FFE
33.5kWh battery pack
CHAdeMO DC Fast Charging

triangles
Posts: 1148
Joined: Tue Aug 16, 2011 11:40 am
Location: Toledo, Ohio

Re: Dead 12V battery then traction control freaks out

Wed Jul 07, 2021 9:27 am

Hi psyclone. Did what work? If you mean the low voltage disconnect, then yes it works. I just "rewired" one of the ad a circuit fuse things to put the low voltage disconnect in line with the F1 fuse. I can sketch up a schematic if you need it. I didn't take any pictures and I'm not tearing it apart again to do so. I did have to pull the fuse block out and dremel part of the plastic away for enough clearance for the add a fuse to be able to fully seat. I only used this for the coldest winter days when I wanted to use the GO times, otherwise I leave the F1 fuse out. I know it worked because about 25%-35% of the time my car was not warm and toasty which indicated the TCU did not shut off and the low voltage disconnect had done its thing. The 12V battery still had enough juice to start the car and I didn't have to use my jump pack. The real danger with this scenario is that a low or discharged 12V battery can freeze if it's really cold out. Having the TCU draw the 12v battery down to 12.1v (40% SOC) is very hard on the battery. They are not designed to be this deeply discharged. A typical starter battery does not like being discharged to less than 80% SOC. Doing this routinely leads to a dramatically shortened life. I assume this is what eventually wore the battery out. After about 3.5 years from when the original was warranty replaced, I noticed the 12V was very weak as it didn't even have enough juice to jump start my motorcycle. I ended up having to turn on the car and the DC-DC converter provided the current needed to jump start the motorcycle. :lol: While it still functioned fine for the FFE I decided to replace it before it failed completely. I went with a LiFePO4 12V deep cycle battery with a BMS that cuts it off at 10V to protect the battery from over discharge. I hope to get 8+ years out of this battery to offset it's $250 price tag. It has worked fine for 2+ months I've had it in there. However I have also had my F1 fuse out the whole time.
2014 Blue Candy FFE
http://www.fuelly.com/car/ford/focus/2014/triangles/303811 (since this forum doesn't allow BBcode in sigs)

Heima
Posts: 161
Joined: Thu Feb 21, 2019 11:46 pm

Re: Dead 12V battery then traction control freaks out

Wed Jul 07, 2021 11:08 am

There might be a firmware update to this problem, or maybe this corrects a bad flash from the factory, not for certain:

SSM 47198
Some 2013-2017 Fusion Energi, 2012-2017 Focus Electric and 2013-2017 C-MAX Energi vehicles
equipped with a TCU built on or before 11-Oct-2017 may exhibit a discharged battery, inoperative
remote features via MyFord Mobile app, incomplete user authorization and/or accessory protocol
interface module (APIM) DTC U0198 with no modem electronic serial number (ESN) displayed. To
correct this condition, perform any open TCU field service actions (FSAs). If U0198 DTC still
remains, remove the TCU fuse for 5 minutes then reinstall. Reprogram the TCU using IDS or Ford
J2534 Diagnostic Software (FJDS) release 108.05 or higher. An internet connection is required.
Calibration files may also be obtained at www.motorcraftservice.com. For claiming, use causal part
14G229 and applicable labor operations in section 10 of the SLTS manual

psyclone
Posts: 8
Joined: Thu Apr 22, 2021 9:36 am

Re: Dead 12V battery then traction control freaks out

Thu Aug 05, 2021 1:08 pm

Thank you both for the most recent replies. Triangles - I pulled the fuse, let it sit over 5 min. and replaced it. So far so good???? HAHA

Heima - Thanks for the info on firmware update. I'll see if the squealer will do this without charging an arm and a leg. I REALLY don't think they know much about the FFE and need to find one who does. There are still A NUMBER of things this car is and isn't doing that have it borderline being sold off.

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