UXXXX codes are related to the vehicle’s communication network. Modern vehicles have multiple control modules (computers) that communicate with each other to ensure smooth operation. U codes indicate problems with the communication between these modules. Here’s a breakdown:

U0XXX: Generic or global codes.

U1XXX: Manufacturer-specific codes.

NOTICE: Due to the massive number of codes in the listing, we have split them up into multiple pages. Choose the section of codes based on the first three characters of the code (e.g., U0071 is on the U0000 through U0099 page).