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Discussion Starter · #1 · (Edited)
This was done on MY18.

I thought this would be a good place to put some instruction for future use and others as when I went searching I had to dig a bit after replacing my battery. Some places (threads, youtube, etc) have misinformation which at the least does not work for the RS USDM cars (or I didn't do it to perfection, but gave these 3 the college try).

Some suggestions I've seen were as follows - but they did not work:
1) Ignition on (engine off), headlight flashers 5 times, then brake pedal 3 times. Battery indicator lamp will flash meaning success.

2) Ignition on (engine off), fog light button 10 times, then hazard button 10 times. Battery indicator lamp will flash meaning success. (this did do something > it will actually honk the horns and activated a calibration of the TPMS starting with left tire)
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3) Ignition on (engine off), lights on, fog light button 5 times, then hazard 3 times. Battery indicator lamp will flash meaning success.

Again, these will not work (on my car at least). If anyone does have a way, I will post the corrected non-ForScan version in this first post.
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non-ForScan reset > @crepr12, @big jim, @GmpaJimj , plus others have have confirmed this method >>
Ignition on
Headlight flash 5x's (this is headlight flash to pass | left arm pull inwards)
Then brake press 3x's
Wait 2 or 3 seconds (up to 10 seconds) and the battery indicator to flash 3x's (giving the indication BMS was reset).
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So one way to reset BMS is to use ForScan. What is ForScan?
READ HERE

There are a couple of area's you can learn more and do some interesting things. Thanks to the collection that @seniorgeek has provided and collected from other members, you can explore more.

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There are a few different ODBII units you can buy out there. Don't know all that work (I could list them all, but not going to search/data mine the forum. If you want to list one you have vetted I will put it here), however I will list the one I have used and works like a charm - it uses wifi for you to connect you notebook to. There is an iPhone app, but I have not purchased it to try (seeing that the Windows version is free).

NOTE for ForScan Lite > @Alpha Dog has confirmed that ForScan Lite v1.5.9 on an iPhone iOS v14.2 appeared to reset the BMS successfully. The battery light flashed two or three times after selecting the BMS reset and hitting the 'play' button. There was a rather scary warning he did mention about, and then it took a few seconds before the battery light flashed. Its worth pausing at that point to wait for it.

OHP wifi ForScan adapter

Now as far as resetting your battery monitoring system follow the info - or DL the same attached PDF. And yes it is a good idea to clear out those DTCs. Capture what you see just before, clear them, go out for a drive or two and check them again and compare.

SIDE NOTE: @Alpha Dog stated that Forscan Lite on iOS has both BMS reset and TPMS training request functions. I will update when this is confirmed
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So, this is like the oil change reminder?
How would the car kill a new battery?
In brief, the BMS is tracking your battery state of charge and age. If you don't reset the BMS, it will hold the old battery parameters and treat the new battery like an aged battery. This may lead to situations of insufficient charging, which can then lead to decreased life of battery.
 

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There are some things that do not need technology. SLA batteries should not be one of them.
 
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We have AGM batteries in our cars, at least from the factory. AGM batteries are sensitive to over and undercharging, which is why I put the charger on the car once a week or if I know that it will sit for a few days.

Beats prematurely buying a $300 battery!
 
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Start stop cars use AGM batteries. AGM is also in the part number for our batteries
 

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None of the secret cheat code combos worked for me either. Luckily Forscan will allow resetting the BMS with a standard license. My trial extended license expired, and they weren't selling the extended license when I was doing this (on the 4th).
 

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Excellent post thanks turbojr74. When using Forscan did the battery lamp flash to confirm BMS reset?

Also adding that Forscan Lite on iOS has both BMS reset and TPMS training request functions (plus more). I have not used them yet to confirm they work, but I'd be very confident.
 

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Excellent post thanks turbojr74. When using Forscan did the battery lamp flash to confirm BMS reset?

Also adding that Forscan Lite on iOS has both BMS reset and TPMS training request functions (plus more). I have not used them yet to confirm they work, but I'd be very confident.
yes battery lamp will flash when it’s successful.
 

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There's probably a way to check battery age on FORScan. That's a way to know for sure.

@morbid you don't have to pay for an extended license, just have to renew it all the time.
 

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Discussion Starter · #17 ·
Excellent post thanks turbojr74. When using Forscan did the battery lamp flash to confirm BMS reset?

Also adding that Forscan Lite on iOS has both BMS reset and TPMS training request functions (plus more). I have not used them yet to confirm they work, but I'd be very confident.
If you do end up testing the Lite on iOS for those, let me know and I will put a confirmed in the OP.
 

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You guys will get a laugh out of this. I called in to my local Ford Dealer Korum ford in Puyallup, WA to get a price quote on them putting in the battery. That way I wouldn't have to mess with the BMS reset. The service advisor told me that she's never heard of the BMS and she needed to check with the shop foreman. The shop foreman told me to just by a battery at Costco and unplug for 10min or more the old one that would reset the BMS system. I got a laugh out of it as I'm sure the RS isn't the only Ford with this set up.
 

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Discussion Starter · #19 ·
You guys will get a laugh out of this. I called in to my local Ford Dealer Korum ford in Puyallup, WA to get a price quote on them putting in the battery. That way I wouldn't have to mess with the BMS reset. The service advisor told me that she's never heard of the BMS and she needed to check with the shop foreman. The shop foreman told me to just by a battery at Costco and unplug for 10min or more the old one that would reset the BMS system. I got a laugh out of it as I'm sure the RS isn't the only Ford with this set up.
I’m in Puyallup @flyingcesar and could help if you need. I would recommend staying away from Korum (long stories).
While it’s more of a drive, I’ve had great service as Scarff Lincoln Ford in Kent. Talk with Gary there. Great guy.
 

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@turbojr74 I ordered a OBII cord and will download FORSCAN. Figured with the money saved from going to the Stealer might as well give a go my self. I'll definitely reach out to you if I hit a roadblock. Thank you for the recommendation ill start dealing with Gary.
 
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