China's troubled Jade Rabbit moon rover "woke up" again early Friday, though the mechanical troubles that have plagued it remain unfixed, the government said.

The rover, called Yutu in Chinese, turns dormant and stops sending signals during the lunar night, two-week periods when the part of the moon's surface it is on rotates away from the sun and temperatures turn extremely cold.

The State Administration of Science, Technology and Industry for National Defence (SASTIND) said on its website that the rover "woke up" from its third such slumber at 6:42 am Beijing time.

The Jade Rabbit is named after the pet of Chang'e, the goddess of the moon in Chinese mythology, and was deployed on the moon's surface on December 15, several hours after the Chang'e-3 probe landed.

The Chang'e-3, which also goes dormant, woke up on Wednesday, SASTIND added.

Jade Rabbit experienced a "mechanical control abnormality" as the lunar night fell on January 25, leading to fears in China it might never revive. To the country's relief, however, it started sending signals again in mid-February.

But the mechanical problem has still not been fixed, SASTIND said Friday.

The Chang'e-3 probe's landing -- the third such soft-landing in history, and the first of its kind since a Soviet mission nearly four decades ago -- has been a source of national pride in China, which has huge space ambitions.

Beijing sees the space programme as a symbol of China's rising global stature and technological advancement, as well as the Communist Party's success in reversing the fortunes of the once-impoverished nation.