Short in the wiring or the starter is defective.
It is very common for the starter to be the cause of that fuse blowing.
The starter has failed.
A failed starter is a likely cause.
If it blows when cranking the starter has failed.
Dead short to ground or an overload
A short in any part of the wiring or in the motor itself can cause the fuse to keep blowing. Don't try a bigger fuse you can start a fire that way. follow the wires from the control box to the seat belt motor and the to the fuse box. If there is any damaged wire replase it with the same gauge wire.
Defective PW motor, short in the wiring or the switch.
Heater blower motor is defective and locked up, or possible short in the wiring.
faulty wiring or too low of a fuse, shorting out because the wire is touching metal or another wire
The control wire to the solenoid may be deteriorated and shorting out. Or, you may have a bad starter.
The fan motor has probably failed.
not usually!!if fuse is blowing out check for short!!