I have a 2008 Toyota Camry 2.4l. My problem is battery is over charging causing amplifier ground wire to blow fuses and also melt the wire, battery tested it is good. Tested alternator and tested bad voltage regulator. Bought a new alternator and tested it before fitting it to car. After putting in car, tested again and it's saying bad voltage regulator. Changed with new alternator 3 times in one day. All tested before put on car and all tested good but once on car, it's tested as bad. Could it possibly be my ground wire to amplifier is not grounded right in the trunk? I can not get any help from anyone because nobody seems to know what the problem is. Please help me someone. Very stressed and confused.
Is this an after-market amplifier?
If so, then I would completely disconnect it (take thorough notes or pictures of the existing wiring) and then re-test the alternator / regulator / charging system.
If that then works properly, then I would look at the wiring to the amplifier. From what you say about the ground wire melting, then I think there is something amiss here.