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Odd the system doesn't read the battery correctly because my BS is on a battery tender and is at full charge. The computer must be only on a vehicle inactive timer.
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Is your battery tender connected to the battery terminal or to the BMS unit? If not to the BMS unit the BS computer doesn’t know the actual charge level.
OP
OP
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- #6
Ok, thanks.
Connected to battery positive side and the negative on the body but not the same ground as the battery.
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Connecting to the battery positive side is not the same as connecting to the BMS.
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I know. Maybe I wasn't clear. The battery tender is connected to the positive side and the negative wire is on the body.
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I used to get the same message on my 2015 Escape with no issues.
I get the same message a couple of times a month when I haven't driven it for4 or 5 days or so.
It's just shutting down non essential things to save battery. No big deal. When you start it, all is restored.
It's just shutting down non essential things to save battery. No big deal. When you start it, all is restored.
I know this is a source of huge debate, but I'll just throw out there, I've had my battery tender connected directly to the positive and negative posts of the battery for nearly three years. I put it on whenever I park for more than 3 days or when I notice the auto start/stop working less during a drive. As it does more now that the car is running lights and such in the winter dark. I've never had an issue with the "charge level" going wonky. I have a voltmeter plugged into the 12v port so I can see what level the alternator is running at. 14.9 is the highest I've seen and 12.1v is the lowest I've seen when the car is autostopped. I got that message one time when the car was almost new and that was what prompted me to get the battery tender hooked up. I have not seen that message since 2021.
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You have the negative line to the battery's negative post where the BSM is. I had it there originally but was told here it would be better on a body ground. I don't remember why but something to do with the BSM negatively( no pun intended).
Yep. I took out the clamping bolts for the cables and put the charger's ring terminal over it and reclamped those to the posts. The charge wires are on the "battery side" of that BSM, despite many claims that you need to hook up and feed current to the battery through it. Maybe your battery is actually dying and so the charger isn't having an effect?
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The charger shows 100% charged. Post#5 explains why the BSM isn't reading the battery somehow. My BS can sit for 2-3 weeks.Yep. I took out the clamping bolts for the cables and put the charger's ring terminal over it and reclamped those to the posts. The charge wires are on the "battery side" of that BSM, despite many claims that you need to hook up and feed current to the battery through it. Maybe your battery is actually dying and so the charger isn't having an effect?
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At the risk of stating the obvious -- in order for the BSM to work properly and be accurate, ALL current flowing into and out of the battery must flow through it. Nothing should be connected directly to the neg(-) terminal.
Also, battery monitors must be 'told' when the battery's SOC is 100%. Apparently the BS does this automatically. From the manual:
"After battery replacement, or in some
cases after charging the battery with an
external charger, the battery management
system requires eight hours of vehicle sleep
time to relearn the battery state of charge.
During this time, your vehicle must remain
fully locked with the ignition switched off.
Note: Prior to relearning the battery state
of charge, the battery management system
may temporarily disable some electrical
systems."
Here's a good thread:
https://www.broncosportforum.com/forum/threads/ford-bms-battery-monitoring-system-how-it-works-how-to-properly-charge-how-to-power-accessories.7576/
Also, battery monitors must be 'told' when the battery's SOC is 100%. Apparently the BS does this automatically. From the manual:
"After battery replacement, or in some
cases after charging the battery with an
external charger, the battery management
system requires eight hours of vehicle sleep
time to relearn the battery state of charge.
During this time, your vehicle must remain
fully locked with the ignition switched off.
Note: Prior to relearning the battery state
of charge, the battery management system
may temporarily disable some electrical
systems."
Here's a good thread:
https://www.broncosportforum.com/forum/threads/ford-bms-battery-monitoring-system-how-it-works-how-to-properly-charge-how-to-power-accessories.7576/
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