Asia shares mixed on central bank uncertainty; Earnings lift Japan

Japan's benchmark index outperformed on Wednesday while the rest of Asian equities were subdued as investors awaited further direction from global central banks

The added 0.8 percent while the Shanghai Composite dipped 0.8 percent. South Korea's Kospi and Australia's S&P ASX 200 ended flat.

"With a lack of first tier data today, the market tone will likely remain one of consolidation and caution ahead of key events later this week: ECB meeting, US Q3 GDP and October payrolls," said Dariusz Kowalczyk, senior economist and strategist of Asia ex-Japan at Credit Agricole.

(Read more: As plenum looms, China's big challenge is a balancing act)

TICKER	COMPANY	NAME	PRICE	CHANGE	%CHANGE
.N225	Nikkei 225 Index	NIKKEI	39,103.22	+486.12	+1.26%
.HSI	Hang Seng Index	HSI	18,868.71	-326.89	-1.70%
.AXJO	S&P/ASX 200	ASX 200	7,811.80	-36.30	-0.46%
.SSEC	Shanghai	SHANGHAI	3,116.39	-42.15	-1.33%
.KS11	KOSPI Index	KOSPI	2,721.81	-1.65	-0.06%
.FTFCNBCA	CNBC 100 ASIA IDX	CNBC 100	9,771.74	+0.82	+0.01%

Investors on central bank watch

The European Commission said it expected the euro zone economy to shrink this year by 0.4 percent, before recovering to grow by 1.1 percent in 2014. The gloomy forecast bolstered expectations for the European Central Bank (ECB) to cut interest rates when it meets on Thursday.

U.S. third-quarter gross domestic product is also due on Thursday, followed by October non-farm payrolls data on Friday.

Meanwhile, a stronger-than-expected U.S. service sector activity on Tuesday reinforced expectations for an eventual reduction in the Federal Reserve's monetary stimulus and led Wall Street shares to snap a two-session rise.

Nikkei up 0.8%

Japanese investors cheered as dollar- yen approached the 99 handle and as speculation rose that Toyota Motor would post strong earnings.

Toyota shares closed up 0.5 percent after public broadcaster NHK said the carmaker would lift its earnings guidance. After the market close, Toyota posted an 82 percent annual rise in interim profit and raised its annual operating forecast by 13 percent.

Nissan Motor ended nearly 3 percent higher after slumping over 10 percent on Tuesday.

(Read more: Will 2% inflation be enough for Japan?)

Index heavyweight SoftBank fell 2 percent on profit-taking while Fast Retailing shed 0.8 percent after reporting a 13.8 percent drop in September same-store sales at its Uniqlo clothing chain.

Meanwhile, minutes from the Bank of Japan's meeting earlier this month revealed that some central bank members felt the pace of gains in consumer prices may slow temporarily.

Shanghai dips 0.8%

China's benchmark index erased earlier gains to approach Tuesday's one-week low ahead of trade data on Friday and this weekend's major Communist Party policy meeting.

Automakers weighed with SAIC Motor leading declines by 3.3 percent after Beijing city officials said they would cut new car sales quotas by nearly 40 percent next year to reduce vehicle emissions and pollution.

But a rally in oil producers capped larger losses. Guanghui Energy jumped 4.6 percent, Sinopec increased over 2 percent and Petrochina added 1.3 percent.

(Read more: China's new plan for growth—less governance?)

In Taiwan, shares of personal computer maker Acer tumbled by the daily trading limit of 7 percent after announcing a new chief executive following it's disappointing third-quarter net loss.

Sydney flat

Australia's benchmark continued its lackluster trend after September's trade deficit came in at A$284 million, narrower than the expected A$450 million.

The nation's top lender by market value, Commonwealth Bank of Australia (CBA) rose 1.2 percent after posting a 13.5 percent rise in first-quarter cash earnings, in line with forecasts.

Department store operator David Jones fell 1.6 percent following an earlier 4 percent decline on media reports that it will extensively review its property portfolio.

Seoul flat

South Korean shares hovered near Tuesday's three-week low due to a 2.3 percent fall in Samsung Electronics shares as it held its first analysts' briefing in eight years.

But a rally in blue-chip stocks capped larger losses on the benchmark index. Hyundai Motor climbed 2.2 percent, Kia Motors surged over 4 percent and steelmaker Posco added 2.3 percent.

India down 0.38%

India's benchmark index finished the session around 20,900 points while the weakened to 62 per dollar.

— By CNBC.com's Nyshka Chandran. Follow her on Twitter @NyshkaCNBC