According to the "Notice of the State Administration of Taxation on Clarifying the Implementation Time for Enterprises to Adjust the Residual Value Ratio of Fixed Assets" [Guo Shuihan (2005) No. 883], the residual value of fixed assets is uniformly determined to be 5.
At the same time, there is a provision in the new income tax law that reads: For means of transportation other than airplanes, trains, and ships, the period is 4 years.
So the depreciation life of the car is 4 years and the net residual value is 5.