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So. Stupid question, how can I tell if my focus has the BMS and smart charging system that needs to be reset? Is there something I should be looking for like a sensor somewhere or is a different type of battery than a standard led acid battery? I've got 2 Foci (13' & 14') both will need batteries before the heat of the summer. Thanks for any assistance!
Both your 2013 and 2014 MK3 have the smart charging system. The US models have conventional lead acid batteries.
 

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Anyone know of a Android version of something similar to reset the BMS with a bluetooth ODB2 and Android phone.

I don't have a laptop. :(
 

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So. Stupid question, how can I tell if my focus has the BMS and smart charging system that needs to be reset? Is there something I should be looking for like a sensor somewhere or is a different type of battery than a standard led acid battery? I've got 2 Foci (13' & 14') both will need batteries before the heat of the summer. Thanks for any assistance!

the first clue will be when you get that msg saying you battery is low to see manual. manual just tells you to replace it i thank. but then you replace it and it still tells you the same thing and one week later still says it and then you start to get annoyed by it because it wont let you use the radio or power ports for no more then 2 minutes. with out the key on.
 

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For a reset of the BMS:
1. Switch on ignition (do not start engine)
2. Switch on dipped beam
3. Press 5x the rear fog light button (do not switch 5x on and off the rear fog light)
4. Press 3x hazard lights button (do not switch 3x on and off hazard lights)
5. Then the battery symbol in the speedometer should flash 3x quickly.
If it does not flash immediately, wait 20 seconds.
Can someone confirm that this method posted by Bud Bundy is working?
 

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So I found a video of a Chinese guy that did this procedure. The confirmation that the BMS was reset is that the battery light will blink.
I did this procedure as I also found reference of it on an Ford focus forum from my country. On this forum they also state that you have to leave your car 8 hour or so parked.
This is the link to the video:
 

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So I found a video of a Chinese guy that did this procedure. The confirmation that the BMS was reset is that the battery light will blink.
I did this procedure as I also found reference of it on an Ford focus forum from my country. On this forum they also state that you have to leave your car 8 hour or so parked.
This is the link to the video:
https://youtu.be/QV9N0hvALyk
There was speculation that this procedure didn't work on NA cars. Has anyone in NA confirmed this works?
 

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Although I already have an ELM 327 and use it to upgrade my display to 5" MFD Navi it was easier to press some buttons.
Hope this works also for NA Focus.
My problem started in summer when my battery died without a warning. Change the battery but did not know of this BMS reset procedure. Now in autumn I started to have Steering assistant fault message popping on the display and the steering assistant starts with delay. I notice that if I turn the key but do not start the engine and delay the start for more seconds then the steering start to operate also normally, no error message. So I suspected an electrical problem of not having enough power even if the engine did start.
On the Ford Focus Romanian forum someone suggested first to try this BMS reset before changing the complete steering rack.
So I tried it yesterday evening after parking the car in the garage.
This morning right after engine start the steering started without delay and the steering wheel could be turned without any effort, smooth.
 

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This might be the BMS reset procedure for cars without rear fogs. Found in an Amazon review of all places. If the link below dies someday, the “manual reset” instructions were loaded in an aftermarket reset scanner that gave instructions for cars with and without a rear fog light button.

https://www.amazon.com/gp/aw/review/B01N4GH6UZ/R20FGGZTBIV03Q?cursor=2

Procedure

Note: Only reset the sensor if the battery was replaced.

Vehicles without rear fog light key:

Perform steps 1-3 within 10 seconds

1. Ignition ON, Engine OFF
2. Activate the headlight flasher 5 times.
3. Fully depress the brake pedal 3 times.

4. If the battery charge indicator lamp in the instrument cluster flashes 3 times in 15 seconds, then the reset was successful.
The procedure for cars WITH rear fogs is the same as Bud Bundy posted earlier, except Bud had an added a step after #1 saying the dipped beams need to be on. So maybe that needs to be in there?
 

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Anyone want to test it out and report back? I would, but aren’t doing a battery right now.

Even better, can FORscan people confirm it’s actually resetting the BMS?
 

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Anyone want to test it out and report back? I would, but aren’t doing a battery right now.

Even better, can FORscan people confirm it’s actually resetting the BMS?
FORscan dose reset it. that method you quoted dont work on the usa cars. but for scan diffidently resets it, it will throw a bunch of fauls positive codes in the processes just clear them and you will be good to go

maby i will make a vid of it next time i have to do it.
 

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My Focus is coming due for a battery can I just replace the battery and call it good. I spoke with 2 different dealerships in my area and they told me That the BMS will reset itself and they never heard of it needing to be reset.
 

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My Focus is coming due for a battery can I just replace the battery and call it good. I spoke with 2 different dealerships in my area and they told me That the BMS will reset itself and they never heard of it needing to be reset.

they will say that but the truth is it wont reset it self you will know it if the 1 hr mode on the radio dont stay on for a full hr. and it may keep throwing the low battery msg at you. they clame they dont know about it and they may not. but trust the ones hear that have these cars you need to manually reset the bms after every change. simple and fast to do. even tells this in the service manual some ware
 

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they will say that but the truth is it wont reset it self you will know it if the 1 hr mode on the radio dont stay on for a full hr. and it may keep throwing the low battery msg at you. they clame they dont know about it and they may not. but trust the ones hear that have these cars you need to manually reset the bms after every change. simple and fast to do. even tells this in the service manual some ware
[poke]

 
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