Lexus Repair: charging system???, 1993 lexus sc400, lexus sc400

Question
1993 Lexus SC400
well car wouldnt start the other night and all i heard was a clicking sound from the starter. and i thought oh man this is bad cause its every lexus v8 owners worst nightmare. but the power seem a little weak so i used a jumper pack and tryed to jump start the car but the engine wont turn over.then i used jumper cables and jumped my car with my friends car and it started but after i took off the cables my car dieds out.so i changed the altenator know that my battery is bad already. after changing it i jump started the car then i took off the cables it died out again. i put my friends battery in my car it started fine and it drove fine. but i still wanted to test the altenator so why the car was running i disconnected the negitive from the battery and the car jus died. i checked the fuses. in the engine compartment a fuse thats 30a "AM2" it looks burnt on the outside and the copper inside looks burnt. i dont know what this fuses does but can it be the problem or is it something else.
Sorry for the long post. Thanks!

Answer
Hello, Depending on what kind of alternator you put in, I see many rebuilts from Checker, Pep Boys that are bad right out of the box. While the car is running is the battery light on inside the car? Was the output voltage to the battery around 13.5-14v? Sounds like you may need to bring it to a quality shop that has a factory trained Lexus tech.