Truck starter common fault?

Three common terminal is connected with the battery cable terminal that big thick called the 30th terminal connected to the DC motor that big thick terminal called C terminal connections have a little thin on the starter that is called No. 50 Post a starter does not start troubleshooting starter and battery cable and battery clamp can be used without problems such as a wire shorted on the 30th and the No. 50 terminal activation instructions starter starter no problem checking insurance, relay , key to the door , and the associated connection 2 starter unable to check the battery power is sufficient to check the battery and the starter cable and various battery clips can be used if there is no problem screwdriver shorting the 30th and C terminals observed motor asked to mention checking whether the brush 3 starter , starter idling a car so flywheel half turn in the car boot as normal startup instructions observation starter is a problem with the flywheel ring gear 2 to be removed to check the starter drive gear is intact 3 check the starter starter apart to check one-way clutch is in good condition and other mechanical parts of the course in the car starter problems are diverse and sometimes you want to be good at analyzing carefully study the problem is very simple