The six-wheeled Yutu vehicle Jade Rabbit began operating last month after making the first soft landing on the moon by a space probe in 37 years.
It was designed to roam the lunar surface for three months while surveying for natural resources and sending back data, along with its stationary lander Chang'e 3.
The mission has been a popular success for China's space programme and the rover has attracted more than 150,000 followers on its microblog. It last posted on Saturday saying repairs were under way and hope was not lost.
The posting said: "Sorry to make you all sad. The engineers and I haven't given up yet."
News of the rover's troubles were splashed across Chinese newspapers yesterday and even featured at the Foreign Ministry's daily briefing. The problems appeared to be related to the solar-powered probe's process for shutting down for the lunar night, which lasts more than two weeks. The temperature during that time drops to -180ÚC.
The probe had survived its first shutdown, during which it relies on a radioactive power source to keep its delicate sensors and other equipment intact.
The rover was traversing a relatively flat part of the moon known as Sinus Iridum, or the Bay of Rainbows, at a speed of 200 yards per hour. The landing vehicle, which has already shut down for the lunar night, is designed to conduct scientific examinations for one year.
Online speculation focused on the possibility of lunar dust having blocked one of the solar panels from folding inward, leaving equipment exposed to the dangerously low tempera-tures. It will not be known if the probe is able to function again until after the two-week break.
China's space programme has made steady progress since the country launched its first manned spacecraft in 2003. Jade Rabbit Yutu is named after a mythological Chinese animal said to live on the moon.