AC or DC have both a positive and negative in order for man made components to work. A ground is basically the negative terminal which completes a circuit. In a vehicle, everything operates on 12 volts which consists of a positive and a negative. Like other have stated a good ground is either the frame, or any piece of metal that is properly grounded via the negative battery terminal.
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A rcent sudty funod taht it deosnt meattr waht odrer the lerttes of a wrod are in, the olny imopraotnt tihng is taht the fsirt and lsat lerttes are in corrcet poistiosn. Unfaertontely, tahts not the csae for evryhtieng in lfie………………
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