Tesla started delivering China-made Model 3 electric sedans from its $2 billion Shanghai factory in December, but some buyers said on Chinese social media that the control units in their cars run on HW2.5 chips, which are less advanced than the HW3.0 chips listed on their specification sheets. The Ministry of Industry and Information Technology urged Tesla on Tuesday to ensure product consistency, quality and safety, according to a statement on the ministry's website. HW3.0 chips are necessary for the full self-driving mode in Tesla's driver assistance system, a feature that is optional when customers order Tesla cars. In a post on its Weibo account last week, Tesla said the swap was due to a lack of supply of the HW3.0 chips and the company would replace the chip for customers who received cars with the HW2.5 systems.