12v battery replacement issues

Zephrant

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Bought a 22GT, had no indications that the 12v battery was bad but didn't want to risk a failure when my wife was driving and I was out of town this winter.
Bought the Ford branded 12v battery from Autozone. Installed with no issues at all.

But I can't get rid of the "Charging system service soon" message that now shows up on every start. I've done the "pull headlight stalk 5 times and press brake 3 times" sequence at least 10 times. I get the "red battery icon flash three times", yet right after it always gives me the same error message again.

Did the replacement two weeks ago, driven 12+ times since then. Charged to 80-85% every night, doors locked and allowed to go to sleep, etc.

Any other ideas on how to reset the system?

As a side note, I used a load tester set to 400 CCA on both the new battery and old. New: 11.25 volts after 10s, old: 11.1v. So the 3 year old battery is only slightly worse at providing current than the brand new one. Both batteries tested after charging to full voltage over 3-4 hours.

Ford Mustang Mach-E 12v battery replacement issues IMG_5374
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Zephrant

Zephrant

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Hooked up an Autel MaxiCOM MK808Z-BT. Cleared some errors "module lost communications", which looked normal. But four errors came back (TPMS is known issue, fixing tomorrow, don't know what the parking brake error is).

B11DB:08
ODDTCS
Battery Monitoring Module A

B11DB:08-0A
CMDTCS
Battery Monitoring Module A

Did a search, and someone said check the negative terminal post. Went out to look, and the little plug was not fully seated, definitely loose. Pushed it in to click, and it looks like it is better now.

So if you have this problem, make sure the little two wire plug is fully seated by the negative terminal.

Ford Mustang Mach-E 12v battery replacement issues IMG_1967


Ford Mustang Mach-E 12v battery replacement issues IMG_1969
 

Mach Al

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I purchased the battery at Advanced Auto Parts to replace the stock battery. The only one they had was a die hard. Are you sure you purchased the OEM replacement? I could not find a replacement for the Mach E from any other auto parts store. I did not install the advanced auto parts battery because it had a different amp hour and I read online that that can cause problems with the BMS system. I went to my Ford dealer and the cost of the OEM battery plus installation was the same cost as the battery at AutoZone so I had them do it.
 


Adventureboy

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Hooked up an Autel MaxiCOM MK808Z-BT. Cleared some errors "module lost communications", which looked normal. But four errors came back (TPMS is known issue, fixing tomorrow, don't know what the parking brake error is).

B11DB:08
ODDTCS
Battery Monitoring Module A

B11DB:08-0A
CMDTCS
Battery Monitoring Module A

Did a search, and someone said check the negative terminal post. Went out to look, and the little plug was not fully seated, definitely loose. Pushed it in to click, and it looks like it is better now.

So if you have this problem, make sure the little two wire plug is fully seated by the negative terminal.

IMG_1967.webp


IMG_1969.webp
Yep, that would do it. BMS had no information which threw the error. Make sure the battery is fully charged and do the BMS reset again to give it a solid starting point.
 
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Zephrant

Zephrant

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Last update- been another week, no issues what so ever.
Nice having a car again with no check lights or warnings.
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