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Discussion Starter · #1 · (Edited)
Hello everyone so I have a 16 st3 69k miles and I notice the battery light came on and I checked my battery and found corrosion on only the negative terminal and I knew it was time to change that battery as well. since it was a ford battery for 2017 I changed the battery and cleaned negative cable/Bms sensor as well. and did the battery reset for the Bms with high beams trick etc and the light still comes back on i also disconnected the grill shutters since I have a code for the active grill shutters and I heard that can trigger the ligh so yea. and still the light doesn’t go away I even checked the fuses and all are good is it possible my bms got damaged from the corrosion? And as far as my battery volt goes it seems good stays between 14.20 and 15v shows in my access port I’ll put pics. Please and thanks guys this thing has me annoyed oh and the picture is before I changed the battery and cleaned it . Oh I forgot to mention when I did reset the bms and leave the battery disconnected for a while it sometimes takes a day or two for the battery light to come back on and sometimes even a few minutes it’s random
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What does the 2 wire connector that plugs into the BMS sensor look like? Are the terminals corroded?
 

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I do know you can't go by the voltage on the accessport. When I put in my ho alt and then left my buddies house the belt broke so I had no water pump and no alternator. AP still said I had voltage it must be reading a command voltage or something.
 

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Discussion Starter · #5 ·
I do know you can't go by the voltage on the accessport. When I put in my ho alt and then left my buddies house the belt broke so I had no water pump and no alternator. AP still said I had voltage it must be reading a command voltage or something.
Hmm well it’s a brand new battery in there now but when I got my old tested at Autozone it still said it was good lol even tho it was throwing out acid I still changed it
 

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Discussion Starter · #6 ·
update: I just ordered the new negative cable at ford so let’s see what happens when it arrives I will let you guys know in a few days if it fixed my problem. Hopefully it does let’s see
 

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Discussion Starter · #8 ·
If you left the AGS connector unplugged make sure that it is clean and dry. Corrosion on those connector pins can cause the battery light to come on.
Wow thanks for telling me I didn’t know and also I just changed my negative cable and so far all my problems have been solved so far! We shall see it’s only been 1 day I will let you guys know now down the line if it comes back on if it doesn’t I’ll confirm it here but so far so good
 

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Discussion Starter · #9 ·
Update: so after 3 days of no battery light of the installation of the negative cable the battery ligh has returned so as of now the only thing I can think of is the error code of my ags not working is possibly the reason I honestly don’t know at this point unless the ags not working makes the light come on I don’t know any ideas? And btw the connection to my bms is fine and the ags connector to the ags looked fine if anyone is curious
 
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