SSM52039 - Unable to achieve 100% state of charge after module replacement

[AI_Speed]

This TSB relates to not being able to charge to 100%. It has nothing to do with miles showing on the GOM (which is not worth looking at, IMO).

No - the charge I mentioned after the reset is how you measure a full level 1 charge to 320 miles ER. Now I get 300 miles as 100% in a warm garage after the CSP battery module replacement(s). Taking trips & using level 2/3 charges 15-85% or so involves GOM measures.

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[Maquis]

No - the charge I mentioned after the reset is how you measure a full level 1 charge to 320 miles ER. Now I get 300 miles as 100% in a warm garage after the CSP battery module replacement(s). Taking trips & using level 2/3 charges 15-85% or so involves GOM measures.

Again…..this SSM is about the inability to achieve 100% state of charge.
I don’t care how many miles show up on (or are missing from) your random number generator GOM. It’s totally irrelevant to this SSM.

 

[The Weatherman]

No - the charge I mentioned after the reset is how you measure a full level 1 charge to 320 miles ER. Now I get 300 miles as 100% in a warm garage after the CSP battery module replacement(s). Taking trips & using level 2/3 charges 15-85% or so involves GOM measures.

I think the issue they are referring to would be seen in the actual % of charge never reaching 100%.

 

[Oneand0]

I think the issue they are referring to would be seen in the actual % of charge never reaching 100%.

Before mine went out and it got towed to the dealership, I made sure to tell them, 2 weeks prior I went from a 100% charge to 96 to 94, then to 86%at most. I’m hoping they get that fixed too, after replacing battery modules.

 

[AI_Speed]

Before mine went out and it got towed to the dealership, I made sure to tell them, 2 weeks prior I went from a 100% charge to 96 to 94, then to 86%at most. I’m hoping they get that fixed too, after replacing battery modules.

So you had the modules replaced once and now you need it again - how many modules replaced?

 

[AI_Speed]

I think the issue they are referring to would be seen in the actual % of charge never reaching 100%.

It may be the same issue though - just another way that the battery module(s) fail over time or right away - in need of replacement once more.

 

[Oneand0]

So you had the modules replaced once and now you need it again - how many modules replaced?

No modules replaced yet. 3 weeks in the shop with no end at this point. It was failing to charge to 100% before it stopped working.

 

[AI_Speed]

No modules replaced yet. 3 weeks in the shop with no end at this point. It was failing to charge to 100% before it stopped working.

Wow that is no fun - so 3 weeks in for 1 recall & 4 CSP's?

 

[MickeyAO]

Hoping @MickeyAO checks out this thread, he could give us a primer on cell balancing processes in a pack.

Didn't bother looking for the original question, but when @TaxmanHog ask you to weigh in, you just do it

As for cell balancing in a battery pack, the BMS will use bleed resistors to discharge individual strings down to the lowest pack string voltage. These can only use very small currents due to the wire size and to ovoid the discharge polarization. So a severally out of balanced strings in a pack could take days using this method. Minor differences should only take minutes to hours.

It sucks when we are cycling a module without a BMS and have to do the balancing manually using resisters.

Strings = cells in parallel; BMS = Battery Management System; polarization = the voltage rebound seen when load is released on a string...doesn't matter if it is charge or discharge.

 

[TaxmanHog]

Thanks Mickey!!

 

[AI_Speed]

Didn't bother looking for the original question, but when @TaxmanHog ask you to weigh in, you just do it

As for cell balancing in a battery pack, the BMS will use bleed resistors to discharge individual strings down to the lowest pack string voltage. These can only use very small currents due to the wire size and to ovoid the discharge polarization. So a severally out of balanced strings in a pack could take days using this method. Minor differences should only take minutes to hours.

It sucks when we are cycling a module without a BMS and have to do the balancing manually using resisters.

Strings = cells in parallel; BMS = Battery Management System; polarization = the voltage rebound seen when load is released on a string...doesn't matter if it is charge or discharge.

Thanks - so what kind of errors and alerts may result if there are problems? I had a CSP battery module replaced 10+ days ago and now can't charge to 320 miles/100% - after a Vehicle / Driving History hold reset right before a level 1 top off charge - it tends to stop at 300 or so - tried a few times.

 

[The Weatherman]

Thanks - so what kind of errors and alerts may result if there are problems? I had a CSP battery module replaced 10+ days ago and now can't charge to 320 miles/100% - after a Vehicle / Driving History hold reset right before a level 1 top off charge - it tends to stop at 300 or so - tried a few times.

If charges to 100%. Then it’s fine. The miles on the GOM don’t matter.

 

[AI_Speed]

If charges to 100%. Then it’s fine. The miles on the GOM don’t matter.

It isn't a GOM issue & it does matter since the battery module replacement seems to be the impact. Level 1 charge in a warm garage always went to 320 before.

 

[Maquis]

It isn't a GOM issue & it does matter since the battery module replacement seems to be the impact. Level 1 charge in a warm garage always went to 320 before.

If you can reach 100% SoC, this SSM doesn’t apply to you. Period.

 

[Ford Motor Company]

Copied from the Mach-E forum:

SSM 52039 2021-2023 Mustang Mach-E, 2022-2023 F-150 Lightning/E-Transit - Unable To Achieve 100 Percent State Of Charge After HV Battery Module Replacement

Some 2021-2023 Mustang Mach-E, 2022-2023 F-150 Lightning/e-Transit vehicles may exhibit a concern where the vehicle is unable to achieve 100 percent state of charge immediately after high voltage (HV) battery module balancing and replacement. This may be due to the battery energy control module (BECM) adjusting the cell balance (conditioning) of the battery module and should be corrected within 22 days. If the vehicle otherwise functions as designed with no related diagnostic trouble codes (DTC) setting, this concern will be corrected automatically with no further actions required by the technician.

----End SSM----

When a cell module in the battery is replaced, it has to have a similar voltage to the rest of the pack so the cells can all work in unison. However, the voltage in the new module may be close but not exactly the same immediately after replacement, which could cause a reduced battery capacity indication. The cell balancing system will work over time to correct the voltage imbalance, which can take up to 22 days.

Effects on % display may also be seen if you suddenly change your usual charge level (e.g. always charged to 50%, but now charge to 90%) or if your vehicle is brand new and has not been fully charged previously. Continue to drive and charge the vehicle normally to the same % level for 2-3 weeks and the fluctuating % behavior should decrease. Temperature effects may also cause a 1% variation when driving starts, this is normal since battery capacity changes due to temperature (pack has changed temp since charging finished).

Hi there, I'd be happy to look into your F-150 concerns on my end. Will you send us a message with your VIN and dealership info? I can look into things on my end.

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