Leonard David obtains some details on the problems with the Chinese Yutu rover from  Yong-Chun Zheng, an associate researcher at the National Astronomical Observatories, Chinese Academy of Sciences : China’s Moon Landing Mission: A Status Check – Inside Outer Space

The primary failure is in the “driving electronics section”:

“The rover cannot move again,” Yong-Chun said. In addition to that, the solar wings of the Yutu rover cannot be folded to keep the inside of the robot warm during lunar night. All other functions of the rover are working properly, he said.

Yong-Chun said that the Yutu rover has experienced very low temperatures during the last three lunar nights. According the designed procedures, the rover has entered into the mode of long-term management.

Meanwhile, Yutu’s panoramic camera and its ground penetrating radar “are working normally,” Yong-Chun reported.