What does it mean?
U2100 is a Network (CAN bus, module communications) fault code. It indicates: Initial Configuration Not Complete - No Sub Type Information . This is a standardised OBD-II code. The technical definition is the same regardless of the make or model of vehicle, although specific causes and symptoms can vary between vehicles.
Symptoms
- Warning lamps appear immediately after a module replacement or a software update
- Features controlled by that module do not work at all
- Vehicle may not start, or may run in a restricted mode
- Scan tool sees the module but reports it as not configured
- Cluster shows unexpected warning messages
- The code returns immediately after clearing
Likely causes
- A module was replaced or reflashed and the configuration procedure was never finished
- Programming interrupted by low battery voltage or a dropped tool connection
- Wrong or generic software loaded into the module
- Used module fitted from another vehicle carrying a different configuration
- Missing vehicle option data, so the module does not know which equipment it must control
- Bus fault preventing the module from receiving configuration data during setup
- Gateway module not updated after equipment was added or removed
How to fix it
- Ask what was recently replaced or programmed, and read the module identification data
- Connect a stable power supply to the battery before repeating any programming
- Compare the module part number and software level with the correct data for this vehicle
- Run the configuration and variant coding procedure through to completion with the proper equipment
- Enter the full vehicle option content, including any factory or retrofitted extras
- Confirm bus communication is stable before programming, otherwise the session will fail again
- Replace the module only if it refuses configuration after a clean, complete attempt