Cali T battery light

Well my 2015 Cali T has a red battery cel - also says Alternator failure . Check w obd and no faults ! Checked out battery ( new 4 mos old ) , alternator , starter - everything checks fine. Car runs fine battery stays charged . Not sure what could be problem - instrument cluster? Help - thanks , james in San Antonio Texas

 

No one has responded- can anyone help me w this problem CEL ? Thanks

 

Thanks , new interstate same as OEM , charging is good

 

Wahhh , still have CeL - alternator failure but car runs great ! Alternator putting out voltage properly, new oem battery tests fine . Dealer just says alternator needs to be pulled- 8 hrs . Alternator is charging FINE !! Driving putting out 13-14 volts . Must have to do w dash sensor that shows fault ?? Don’t know what to do .

 

Huh ? Doesn’t the alternator have a diode rectifier circuit that filters out ac , Steve ? Maybe you’re saying if there is ac voltage that means problem with diodes? I will try it . Thanks

 

Hi Steve , you are a genius!! Nobody, including AD could tell me what the problem is . Yep am seeing 30 Volts Ac at battery. Rebuilder here says they can’t get diode pac :-(( . Also this thing requires pulling suspension parts just to get it out . Any way I might put an external diode or rectifier in line where battery is?? Or if the ac doesn’t hurt anything - how could I turn off dumb light ?? Thanks so much, Steve , james

 

Wow , yep I figured that Steve. I have been driving it til now and me thinks I have been fortunate I didn’t burn something up.I have to drive her to the guy who will r&r alternator . Do you happen to know on the 4 leads to the hot side of battery, which one could I dis connect to dis connect the naughty alternator and run for a short time on battery? Thanks so much , james

 

Wahhh , just had Ferrari dealer install brand new alternator 1500 bucks and guess what - still have alternator light !! Can’t be reset !! Now what ?? :-((
Ps charging fine :-(

 

Hi Steve - you won’t believe this :Wahhh , just had Ferrari dealer install brand new alternator 1500 bucks and guess what - still have alternator light !! Can’t be reset !! Now what ?? :-((
Ps charging fine :-(

 

Yep

 

well I have in another shop that has computer that should reset but it won’t. BTW I checked ac voltage on my new GMC Denali truck idling w lights on - guess what? 30 volts ac ! Wow ! Now put in new alternator and Stll have same cel - don’t know what to do -they are suggesting new ignition ECU :-(

 

Hmm ok

 

So now what ?? I have a shop now telling me they Think it is the main ECU ? Don’t know what to do .