Yutu was ferried to Luna by way of Chang`e in December 2013
The Wikipedia article on the mission writes to say the mission duration for the lander, and rover were as follows.
- Lander: 1 Year
- Rover: 3 months
After Lunar land-fall on December 14th 2013 ADG, Yutu purportedly suffered a mechanical failure in January leaving it immobile within sight of the Lander.
This report writes to say
Its functionality has been weakened considerably by the bitterly cold lunar nights after the rover experienced a "mechanical control abnormality" in January
The same report writes further to say
"With each lunar night, the functionality of Yutu is yet again weakened"
The Wikipedia article for Yutu lists the following systems/instruments
- Ground Penetrating Radar
- Camera Pair
Besides the twin mechanical failures leaving Yutu immobile and it's Solar Panels unable to lock-down - what other instruments/systems aboard the rover have suffered degradation/demise over the last 7-odd months?