Toyota has resumed vehicle production at all its plants in Japan for the first time since the earthquake and tsunami on 11 March.
However, the factories will operate at only half their capacity because of a shortage of spare parts.
The company is unsure when full production will resume.
Since the disasters, Toyota has been operating only three plants with a limited output.
Toyota says it has been struggling to acquire about 150 different types of auto parts and has suffered a production loss of 260,000 cars.