This is most likely because the alternator is frozen. Could be a bad bearing. You be bet is to replace it.
If it is noisy, loose, or hard to turn, it is bad.
There are two bearings in an alternator. One (the large one) is a standard ball bearing arrangement. The other is pretty small and is a needle bearing type. Neither are really serviceable. You would have to disassemble the alternator to do it and by the time they need it the alternator is generally shot anyway. If you are hearing a squeal from that area it probably is not the alternator anyway. It is probably the belt tensioner next to the alternator and they cannot be repaired either.
probably it can be changed but if you change the whole alternator you will gain a new alternator for your engine in opposite of changing only the bearing which is not guaranteed.
The drive belt on the alternator of a 94 Toyota Corolla won't turn if the bearing has seized. The alternator will need to be replaced.
Possibly if the bearing is bad it will freeze up and stop when the bearing gets hot from friction.
Bearing failure. Have the alternator tested. describe the whine - is it proportional to the speed? It oculd be because of the load and the charging - how is your battery condition? Did it do this before? Bearing failure. Have the alternator tested. describe the whine - is it proportional to the speed? It oculd be because of the load and the charging - how is your battery condition? Did it do this before?
No. Completely different systems which aren't connected to each other.
BAD BEARING IN A BELT DRIVEN ACCESSORY? I.E. ALTERNATOR, WATER PUMP, P.S. PUMP, ETC.? BAD BEARING IN A BELT DRIVEN ACCESSORY? I.E. ALTERNATOR, WATER PUMP, P.S. PUMP, ETC.?
It could be a bearing in an idler pulley.
Remove the serpentine belt and check the belt and pulleys for damage. While the belt is off, turn the alternator by hand listening for the noise.
A smoking alternator is usually repaired by replacing the regulator, diode pack, brushes, and bearing. For more severe damage, a new or refurbished unit must be used.