Alternator fail test result question

[Chiefthepup]

Forgive me in advance I’m no expert I’ll just lay out the events and see what you guys think.
under 14k miles bought new.

got recall done on Friday. Went on road trip. Towards end of road trip hit a Main Street area where I had to float around 10 mph and the bronco began shuddering like crazy any time it hit exactly 10 mph.
saw online that a bad battery could have those symptoms (maybe?) and bought a tester this morning. These are the results. Alternator failed the charging system test. Gonna take it in today and drop it off and hope for the best. Just curious if any one here as any insight on if a bad alternator would cause those symptoms.

 

[Ford Motor Company]

Forgive me in advance I’m no expert I’ll just lay out the events and see what you guys think.
under 14k miles bought new.

got recall done on Friday. Went on road trip. Towards end of road trip hit a Main Street area where I had to float around 10 mph and the bronco began shuddering like crazy any time it hit exactly 10 mph.
saw online that a bad battery could have those symptoms (maybe?) and bought a tester this morning. These are the results. Alternator failed the charging system test. Gonna take it in today and drop it off and hope for the best. Just curious if any one here as any insight on if a bad alternator would cause those symptoms.

Hello, I would like to take a further look into your failed alternator on my end. Could you please send us a message with your VIN and mileage?

 

[Dude]

If that is the viking battery system analyzer from Harbor Freight it has good reviews but I would use it on a 2nd and 3rd vehicle just to be sure you aren’t seeing issues with the analyzer

Your battery voltage is relatively low so you could do a drive for about 30 minutes then retest the battery and charging system

What was the order of these? I think the shudder occurred before the 24S24 Recall but I’m not sure:

RDU issue
Recall 24S24 BCM/PCM Calibration completed
Possible transmission shudder
Possible alternator issue

Also, when the 24S24 Recall was completed the transmission controller is supposed to have been reset by the Tech causing the transmission to go through a drive relearn cycle and just suspicious if that relates to the shudder you are experiencing.

 

[Chiefthepup]

If that is the viking battery system analyzer from Harbor Freight it has good reviews but I would use it on a 2nd and 3rd vehicle just to be sure you aren’t seeing issues with the analyzer

Your battery voltage is relatively low so you could do a drive for about 30 minutes then retest the battery and charging system

What was the order of these? I think the shudder occurred before the 24S24 Recall but I’m not sure:

RDU issue
Recall 24S24 BCM/PCM Calibration completed
Possible transmission shudder
Possible alternator issue

Also, when the 24S24 Recall was completed the transmission controller is supposed to have been reset by the Tech causing the transmission to go through a drive relearn cycle and just suspicious if that relates to the shudder you are experiencing.

Thank you for your detailed response honestly.
it’s always shifted super rough between 1st and 2nd. the shudder didn’t start til after the recall. this shudder felt exactly like right before a car breaks down.
I should also note that 2 times in the past 3 weeks I heard a pretty loud thunk noise that came from underneath the vehicle towards the rear/middle while shifting from first to second.
just dropped it off at the dealership and they said they are averaging a 5 day turn around time on diagnostics so I’ll keep yall updated

 

[Mark S.]

Does this tester take into account modern battery management systems (BMS)? The BMS in your car is programmed to reduce voltage output under specific conditions. Reducing alternator output reduces the amount of horsepower required to drive it, thereby increasing fuel economy. I'm fairly certain the BMS in our cars is a big part of the battery/electrical systems people have been experiencing, namely that it's preventing the alternator from outputting high enough voltage to recharge the battery while the vehicle is in operation.

 

[Chiefthepup]

Does this tester take into account modern battery management systems (BMS)? The BMS in your car is programmed to reduce voltage output under specific conditions. Reducing alternator output reduces the amount of horsepower required to drive it, thereby increasing fuel economy. I'm fairly certain the BMS in our cars is a big part of the battery/electrical systems people have been experiencing, namely that it's preventing the alternator from outputting high enough voltage to recharge the battery while the vehicle is in operation.

That’s a great point! To be honest I highly doubt it does. It’s just a harbor freight tester that I’m taking with a grain of salt. I mainly wanted to see the health of my battery and how it does under a load which both came out just fine so I’m gonna assume you are closer to the correct answer.

 

[Chiefthepup]

Does this tester take into account modern battery management systems (BMS)? The BMS in your car is programmed to reduce voltage output under specific conditions. Reducing alternator output reduces the amount of horsepower required to drive it, thereby increasing fuel economy. I'm fairly certain the BMS in our cars is a big part of the battery/electrical systems people have been experiencing, namely that it's preventing the alternator from outputting high enough voltage to recharge the battery while the vehicle is in operation.

UPDATE:
Dropped it off on Tuesday with no appointment. Was told they are averaging 5 day turn around time. Got it back today (3 days later ?) I’m not sure what was done per the work order (performed transmission relearn) but the tech felt the rough shifting and shudder as well which was extremely validating. Whatever he did to fix it worked 100%. Shifts like a dream now. Everything all taken care of and loving my sport again ?
I’m assuming the tester didn’t account for the newer bms systems cause nothing is said about a bad alternator.

Work order for reference for anyone who understands it.

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