Reset BMS

[ZBOBMAN]

Went out of town for a few weeks and received a notice from FordPass that my car went into hibernation to save battery power. car starts up ok and runs but my front turn signals are not flashing, The rear ones work fine. How do you reset the BMS.

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[rugedraw]

Went out of town for a few weeks and received a notice from FordPass that my car went into hibernation to save battery power. car starts up ok and runs but my front turn signals are not flashing, The rear ones work fine. How do you reset the BMS.

Ignition on/engine off. Flash high beams 5 times, then press brake pedal 3 times.

Ensure you battery is fully charged to 100% before you do a BMS reset.

 

[smurfslayer]

Deep sleep mode just disables remote features. I got my first deep sleep alert on my 2017 Raptor last week- stock battery. Started and drove fine, took her to the beach the next day.

take a 30 minute drive before doing anything else, shut down for a few hours and see if everything is back to normal at next start. If not, then check for codes, maybe reset BMS.

 

[Ford Motor Company]

Went out of town for a few weeks and received a notice from FordPass that my car went into hibernation to save battery power. car starts up ok and runs but my front turn signals are not flashing, The rear ones work fine. How do you reset the BMS.

Hi there, if you’d like further assistance regarding the battery concern, feel free to send us a private message with your VIN and local Ford dealer. Thank you!

 

[roadpilot]

Ensure you battery is fully charged to 100% before you do a BMS reset.

^^^ This 1000%

 

[Skye]

The following is the process I've used.

When I first attempted, it wouldn't complete. But then I re-read the instructions (LOL). Line 1: "...within 10 seconds." By finishing steps 1-3 in 10 seconds, the reset went fine.

Without driving, my car will go into Deep Sleep at about the 13-day mark no matter what (tender or no tender attached). Coming out of Deep Sleep is as simple as unlocking the car. I've not had problems afterwards. Hopefully, your experience was a one-off.

Procedure must be carried out within 10 seconds:
1 Switch ignition on (engine off)
2 Pull and release high beam 5 times.
3 Press and release brake pedal 3 times.
4 If successful the battery light will flash 3 times within the next 15 seconds
5 BMS reset completed.
I'm not any kind of expert, but my battery icon flashed three times after performing these steps, so the procedure appears to work. YMMV

Edit,

For those unaware, the Battery Management System (BMS) is like the Oil Life Monitor for the car's battery and charging system. Sometimes, it's necessary to reset BMS.

For example, when the vehicle's battery is replaced, the car or truck needs to know what. Starting new, a battery holds it's state longer, takes less effort (voltage) to charge up, etc. But over time, any battery becomes less efficient, requiring more voltage, sometimes for extended periods. The BMS is the long-term reference and monitor for that. "This battery is 2 years and 8 months old. It needs a higher voltage for eight minutes versus five, to reach a certain State Of Charge (SOC)." If replacing a battery and not resetting, there's a chance the vehicle's system could begin overcharging that new unit.

And, there are also times when things get a bit funky. Like rebooting a computer, a BMS reset might be helpful. It's a simple, user-possible step which could clear some faults. As the BMS involves not only the battery but the vehicle's charging system, any number of components could be effected by a BMS not working correctly. Fortunately, BMS weirdness doesn't happen often.

For those attaching hook-ups and connections for tenders and chargers, read the installation instructions beforehand. Connecting the right way puts BMS in the loop, makes it aware the tender is attached, so things continue to operate correctly.

If considering moving to a lithium battery to save weight, study that topic before doing so. With the S550, there were cases that, given the vehicle and options, BMS didn't care for the lithium unit. The new battery was fine. Lithium batts are used everywhere. But there were some examples where the car's systems just didn't operate the same afterwards. No damage. Just lights, warnings, things not working quite right.

YMMV.

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