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Arent you able to reset the bms just by letting the car sit overnight or unused for a specific period of time(x amount of hours) without the use of a scanner or forscan?
Pretty sure i read that in a thread before with that being procedure mentioned.
 

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Arent you able to reset the bms just by letting the car sit overnight or unused for a specific period of time(x amount of hours) without the use of a scanner or forscan?
Pretty sure i read that in a thread before with that being procedure mentioned.
some cars maby but no these ones hence the service manual entry
 

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I got some weird things going on with my battery.. sometimes when go to my car, before I unlock I see on the screen, a little status bar and it says "shutting off car to save battery" but it's been on all night and then when I start the car, it's like the battery is drained, pushbutton start takes like 3 or 4 seconds of cranking..if I press pushbutton once to power acessories with car off, it turns off after not even 4 minutes.. used to stay on for 10 to 15.. battery is still testing good, it's 590CCA, testing around 520CCA but close to replace... anyone have any good recommendations for batteries, I would like a AGM type with more CCA then oem. Optima redtop used to be a go to, they are not as good anymore and too expensive
 

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I got some weird things going on with my battery.. sometimes when go to my car, before I unlock I see on the screen, a little status bar and it says "shutting off car to save battery" but it's been on all night and then when I start the car, it's like the battery is drained, pushbutton start takes like 3 or 4 seconds of cranking..if I press pushbutton once to power acessories with car off, it turns off after not even 4 minutes.. used to stay on for 10 to 15.. battery is still testing good, it's 590CCA, testing around 520CCA but close to replace... anyone have any good recommendations for batteries, I would like a AGM type with more CCA then oem. Optima redtop used to be a go to, they are not as good anymore and too expensive

battery testing good but is your alternator ? also with the tools you use to reset the bms you can also use it to look at the errer codes on both low speed and high speed can bus.

thats right them $10 cheapo scan tools at walmart dose not pick up or read all the errer codes.
 

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I just picked up this code scanner. It had an option to reset the battery monitor. I used it when I replaced the battery in my car. I believe it worked.

I only had the radio turn off once after a few minutes. Haven't tried for any length of time but I haven't noticed any issues. Battery the first day seemed to be charging normally. The old battery was consistent at 14.6-7 volts, the new one was more variable, but that makes sense to me. Will have to check it again.
 

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i have gotton the low battery a few time since i first reset it. just do a quick reset and it all works like it should again lol. i thank they make it so you would thank its bad when its not. i reset it like 3 time so far with the same old battery in it. still works as it should each time
 

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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.

just to show more proff right from my copy of the manual
 

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After some shopping around I found that I'll just take the car to the dealership for a battery replacement. A battery from O'Reilly is 129 and a battery from Autozone is 159. The dealership told me it's 150 plus tax to replace the battery so that's the route I'm going to take. Thanks everyone for the info.
 

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After some shopping around I found that I'll just take the car to the dealership for a battery replacement. A battery from O'Reilly is 129 and a battery from Autozone is 159. The dealership told me it's 150 plus tax to replace the battery so that's the route I'm going to take. Thanks everyone for the info.
keep in mind they may or may not reset the bms and if they dont they may fight you about it.
 

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You DO realize of course that no car will run forever without 'resetting the battery' on its' own right? The alt does it on its' own or it is not working correctly. Impossible not to.

Ford just created one more gimmick to scare people to go to the dealers there.

Let the car sit with new battery in it at least 8 solid hours and may need more, then problem is gone. Without Ford's quick reset method the battery does it by itself but a time based thing.
 

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You DO realize of course that no car will run forever without 'resetting the battery' on its' own right? The alt does it on its' own or it is not working correctly. Impossible not to.

Ford just created one more gimmick to scare people to go to the dealers there.

Let the car sit with new battery in it at least 8 solid hours and may need more, then problem is gone. Without Ford's quick reset method the battery does it by itself but a time based thing.
yeah tell that to mine that will go for yrs with out auto resetting. its in the bloody shop manual what more proof do you need. they dont auto reset and fyi cars will run fine like they always have with them not reset. only thing it effects is the accessory like the 1hr mode and such.
 

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when doing the bms reset it resets the computer for the age of the battery, so this only needs to be done when a new battery is being fitted, when dealers have said leave it it will reset they are getting confused, it wont reset the bms but it recalibrates

Battery Monitor Sensor

"The Battery Monitor Sensor measures temperature, voltage and current throughput of the battery. It uses this information to calculate the battery SOC (State of Charge). To function with high accuracy, the Battery Monitor Sensor must be recalibrated at regular intervals. A recalibration occurs during a rest period when the battery quiescent current is less than 100mA. This rest period must last for at least 3 hours. The longer the rest period, the greater the accuracy.
The timeframe in which a recalibration must take place is seven days. If the system has been unable to carry out a recalibration within 7 days, the SOC accuracy cannot be guaranteed. This will result in the Start – Stop and SRC systems being deactivated."

with batteries they do wear over time you cant tell everything from just voltage and Checking CCA you need to check capacity too, for example i have a 110ah leisure battery, voltage it could hold at 12.8v and using a digital drop tester cold cranking amps were good and internal resistance was showing good too, however doing a test with a 21w bulb the voltage dropped to about 10.5v in under an hour
 

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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.
By "Activate the headlight flasher", do you mean flash the highbeams or do you mean press the hazard lights button?
 

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I bought a new oem battery for my '12 Focus SE sedan. Before changing the battery in the test mode screen I had no DTC. After replacing battery I have a DTC code. I don't have engine light on, car shifts fine, my windows work and TPMS are fine. I did not do BMS. I have torque pro but don't see an option for this, has prettt much everything but bms. Battery shows proper voltage when off and when on but I have this new DTC code. What ya guys think??
 

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I tried this method and it sent me to a test screen to train my TPMS


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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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



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?
Sorry to be stoopid but what is a headlight flasher?
 
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