TOKYO, July 29 (Reuters) - Japan's Nikkei reversed its course to close slightly lower on Friday, as concerns about corporate earnings grew after Toyota supplier Denso cut its outlook, while a firmer yen also weighed on exporters.
The Nikkei share average settled 0.05% lower at 27,801.64 after rising 0.7% earlier in the session. The index inched down 0.4% for the week.
The broader Topix fell 0.44% to 1,940.31 and posted a 0.8% weekly loss.
The stronger yen and Denso's earnings soured the mood, said Jun Morita, general manager of the research department at Chibagin Asset Management.
"Since Denso's outlook was negative, we would imagine Toyota's outlook may not be positive," he said.
Shares of Denso, a major supplier to Toyota Motor Corp, slipped 5.2% after the company lowered its operating profit forecast for the current business year by 14%.
Toyota edged up 0.56% but rival Honda Motor fell 1.43%. Hino Motors lost 6.53% and Mitsubishi Motors dropped 5.74%.
NEC fell 7.47% to become the worst performer on the Nikkei after the computer maker posted a quarterly loss.
Advantest rose 4.11%, limiting the Nikkei's decline after the heavyweight chip-testing equipment maker raised its outlook and announced a share buyback.
There were 85 advancers on the Nikkei index against 137 decliners.
The volume of shares traded on the Tokyo Stock Exchange's main board was 1.34 billion, compared with the average of 1.2 billion in the past 30 days. (Reporting by Junko Fujita; Editing by Subhranshu Sahu)