Sony Corp said it would partially restart a lithium ion battery factory in Tochigi prefecture on Tuesday, leaving six plants, which make a range of devices from integrated circuit cards to Blu-ray discs, still closed.
The consumer electronics giant is one of dozens of Japanese companies to shut factories and slash output following the March 11 earthquake and tsunami which have disrupted supplies.
Nissan Motor Co , Japan's No.2 automaker, restarted limited operations at five plants in Japan on Monday, with vehicle production expected to start later in the week.
Japan is reeling from a humanitarian and nuclear crisis after the 9.0 magnitude earthquake and tsunami. The country is a key supplier to the global auto and technology industries.
Nissan said in a statement it would resume production of repair parts and parts for overseas manufacturing at its Oppama, Tochigi, Yokohama, Kyushu and Nissan Shatai plants.
Vehicle production is planned to start on Thursday and will continue while supplies last, it said.
Restoration of its Iwaki engine plant, in northern Japan, is expected to take longer than the other plants, it added.
Nissan makes about 22 percent of its vehicles in Japan. Goldman Sachs has estimated the profit impact for stopping production to be about 2 billion yen ($24.8 million) a day for Nissan.
Toshiba said on Monday output was still halted at a factory in Iwate prefecture making system LSI chips for microprocessors and image sensors. It has begun work to bring the factory back on line, but has no timeframe to resume output.
Toshiba said an assembly line at a plant in Japan making small liquid crystal displays for smartphones and other devices will be closed for a month to repair damaged machinery.
Sony is not sure when its plants will resume operations. Some of the plants' output is supplied to other manufacturers, including customers overseas.
Renesas , the world's No.5 chipmaker, has halted operations at 8 of its facilities and is also unsure when production will resume.
The company said it was unlikely to start some of its plants until the threat of power cuts, expected to last until the end of April, diminished.
($1 = 80.610 Japanese Yen) (Writing by Lincoln Feast, Editing by Editing by Ian Geoghegan)