2005 trailblazer battery is not charging starter is good wires are good belt is good connections are good so why is it not charging the battery
Have you tested the alternator?
Also test battery. If it's failing may not be able to hold a charge. If both battery and alternator test ok then I would advise you to do an amp draw test. You might have something draining the battery down while it's parked for extended period of time. Do you have any aftermarket items plugged into power outlet that stays on when vehicle is turned off? If so unplug them when not driving and see if problem goes away.
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