Check charging system

Hello, The dealer didn't tell you what the issue is even though you paid for their services...? Either way, the light is turned on when the computer reads lower than needed voltage, so there may be a bad connection, bad new alternator, or the ECU may be having issues. Did you replace the alternator before the issue came on? You very well could have gotten an alternator that does not support this function, due to design or failure. Can you post any codes present here?