No alternator output at idle?

[J-Dub]

Well, you might want to unplug your BMS also just to make sure your alternator is not the problem. After unplugging BMS, "charging system service soon" will appear at startup. Voltage should always be 13.5V or higher.

Im having am having a hard time researching the BMS module. I think it goes by "battery current sensor" also but it's attached to the negative terminal which may give it a different part number than what's listed on it (L1MT-10C652-AA). If you are under warranty, you may want to have them look at it. Ive owned my ST since new and for the first 4 years, it never dipped below 12.6V with the car running.

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Update: Benny @ Levittown Ford found the part for me!
https://parts.levittownfordparts.com/oem-parts/ford-battery-management-system-l1mz10c679b

I have that same : Service Charging System Now msg. But my cig lighter adapter is showing 14-14.4V with lights , AC and radio playing. Checked adapter against my other car and its accurate. What is going on ? '21 King Ranch 3.0L Ecoboost has only 11K miles.

 

[jwuonog]

Did you ever end up fixing this? I just got the same message last night.

Just following up to this, a year later. That light went away on its own and never returned. No idea what it was.

 

[J-Dub]

Just following up to this, a year later. That light went away on its own and never returned. No idea what it was.

So , I have to ride around for a year looking at a red battery warning symbol ? Ok , got it. Fix Or Repair Daily