Wtf is going on with my BMS

[sms2022]

Accidentally left the ignition on overnight and the BMS went into protect mode. It would not let the battery charge from my tender so I unhooked the battery and charged it outside the car. Since then, the car started once but would not restart even though the battery is 12 volts. What gives?

Should I reset the BMS? Can I just disable the BMS through Forscan so this can’t happen again?

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[Farkel]

I don't know how the BMS would, or could, prevent the tender from charging the battery. I would suspect the battery is the cause of the problem.

 

[sms2022]

I don't know how the BMS would, or could, prevent the tender from charging the battery. I would suspect the battery is the cause of the problem.

I don’t either but that’s my speculation since I connect the charger, it charges for a minute or so, something in the fuse box clicks, then it stops charging. Weird. And ford wants the car towed in instead of just giving me a new battery

 

[17gt07]

Have the battery load tested. I’m willing to bet the battery is bad.

 

[sms2022]

Dammit. Guess the car will be getting towed into ford.

 

[sms2022]

I guess I’ll charge it up tonight and throw it in the car tomorrow morning to go to work and ford can come pick it up from there.

This will mark its 4th time in the shop in the past month for warranty issues.

 

[ORRadtech]

I don’t either but that’s my speculation since I connect the charger, it charges for a minute or so, something in the fuse box clicks, then it stops charging. Weird. And ford wants the car towed in instead of just giving me a new battery

I don't really blame Ford for wanting to put hands on the car to verify the battery is the problem.

I am curious how you have the charger wired in. I always put both leads directly on the battery terminals. No chance any monitor can affect charging then.

 

[sms2022]

I don't really blame Ford for wanting to put hands on the car to verify the battery is the problem.

I am curious how you have the charger wired in. I always put both leads directly on the battery terminals. No chance any monitor can affect charging then.

That’s how I have it. However thinking about it more the car tries to kick on the headlights and taillights and all monitoring systems at once as soon as the charger is connected which I think puts the charger into battery fault mode as it sees a huge voltage drop at once.

I understand fords position but I haven’t had the car except one week this month and it’s been all electrical issues. Very frustrating.

Im just buying an interstate battery for now and I’ll worry about getting the motorcraft battery replaced later. I can put the interstate in my ‘68 once the motorcraft gets replaced.

 

[_zOmbIE_]

I had issues last winter getting my battery tender (Noco) or my smart charger (a Schumacher) to charge while the battery was connected to the car, both would just say "bad battery". So I had the battery disconnected from the car all winter. I posted about it on here, but nobody could explain why it was misbehaving.

This year, it charged fine all winter using the Noco, while connected to the car *boggle*

I would suggest disconnecting the battery from the car and try charging it before I'd take it to the dealer.
*edit* NVM, I see you did that lol

 

[DougS550]

I don't really blame Ford for wanting to put hands on the car to verify the battery is the problem.

I am curious how you have the charger wired in. I always put both leads directly on the battery terminals. No chance any monitor can affect charging then.

I thought I read in the manual, NOT TO connect the ground charging cable directly to the battery Negitive terminal, but yet conect to a side or alternate grounding point. Something about ford had the BMS sensor located on the battery ground side.

 

[Finally21]

That’s how I have it. However thinking about it more the car tries to kick on the headlights and taillights and all monitoring systems at once as soon as the charger is connected which I think puts the charger into battery fault mode as it sees a huge voltage drop at once.

I understand fords position but I haven’t had the car except one week this month and it’s been all electrical issues. Very frustrating.

Im just buying an interstate battery for now and I’ll worry about getting the motorcraft battery replaced later. I can put the interstate in my ‘68 once the motorcraft gets replaced.

So this guy from Enthusiasts Garage says you should not attach directly to the battery cables. Starts around 1:12 in.

 

[WItoTX]

Disconnect your battery, then try charging the battery. If it doesn't charge, your battery or the charger is the issue.

Try connecting charger to another vehicle that works. Does it charge that vehicle? Then you have validated it to be either the charger or the battery.

 

[ORRadtech]

I thought I read in the manual, NOT TO connect the ground charging cable directly to the battery Negitive terminal, but yet conect to a side or alternate grounding point. Something about ford had the BMS sensor located on the battery ground side.

So this guy from Enthusiasts Garage says you should not attach directly to the battery cables. Starts around 1:12 in.

Yes, I know what Ford says and why. I don't particularly care if the BMS system is unaware the battery is fully charged. I've read too many accounts of the BMS interfering. If they are true or not, idk, but the BMS is one of the systems on the car that I don't feel is all that useful or effective.
My opinion only, y'all do what you want.

 

[MrMike]

I thought I read in the manual, NOT TO connect the ground charging cable directly to the battery Negitive terminal, but yet conect to a side or alternate grounding point. Something about ford had the BMS sensor located on the battery ground side.

Yep. Standard spot on these cars is to connect the ground wire to the passenger side strut tower where there is another ground.

https://www.mustang6g.com/forums/threads/simple-but-clever-ctek-battery-tender-panel-install.114063/

I've been charging mine this way for years now, had my car since new.

 

[KeyLime]

Do you have a volt meter? Charge the battery out of the car, let it sit for 8 hours and read the voltage. Refer to the chart. If the state of charge is good you might want to try a load reading. Crank the car and have someone read the voltage across the terminals. If it's 9 volts or less the battery is shot. This of course assumes the car's electronics will allow the starter motor to engage with a weak battery.

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