Manufacturer-Specific Diagnostic Codes List

VW U1501 shows VW-specific gateway module CAN communication fault.

GM U1000 indicates Class 2 serial data communication lost between BCM and ECM.

GM U1010 indicates missing transmission control module data on GM Class 2 network.

GM U1040 indicates BCM detects network fault caused by battery voltage irregularities.

GM U1100 indicates a module lost sync with gateway module in GM vehicles.

GM U1101 indicates BCM fails to communicate with TCM in GM vehicles.

GM U1102 indicates inconsistent communication between multiple modules on GM Class 2 network.

GM U1200 indicates sensor data lost or corrupted on GM Class 2 network.

GM U1201 indicates ECM sending invalid data to BCM in GM vehicles.