What causes the fuses to keep blowing after replacing them in a 99 CamryPwr windows and odometer fuses?

ANY TIME a fuse BLOWS REPEATEDLY on replacement, a severe SHORT CIRCUIT in the circuit served by that fuse IS THE CAUSE. There could many causes of THE short circuit. A couple of the more common causes are: 1. A "hot" wire in the circuit has had the insulation cut or chaffed through, allowing the bare metal conductor [wire] to come into contact with a grounded metal part of the body sheet metal. 2. A device [switch, connector, a lamp [bulb] socket], motor or similar, in the circuit has developed an INTERNAL short, usually due to overheating and/or corrosion. Number one usually happens when a hot wire is pinched or crushed between two sheet metal panels, or the wire [conductor] makes a very sharp turn or bend around a sharp grounded metal edge, and tension and/or vibration eventually chaffes through the insulation, allowing the hot conductor to contact the grounded sheet metal or brace which damaged the insulation. Failure number two usually occurs as the result of material and/or manufacturing defect[s]. j3h.