Code U0103 on the 2020 Chevrolet Silverado indicates lost communication with the gear shift control module. This module manages the electronic shifter mechanism, translating driver gear selection into signals that the transmission control module uses for gear engagement.
Electronic Shifter System
The 2020 Silverado uses an electronic shifter that communicates gear selection requests over the CAN network. The gear shift control module reads the shifter position and sends commands to the TCM. When communication is lost, the TCM doesn't receive gear requests, creating a potentially dangerous inability to change gears or verify Park engagement.
Warning Signs
With U0103 present, the gear indicator on the dashboard may show incorrect or no selection. The vehicle may not shift out of Park, or conversely, may not recognize when Park is selected. Warning messages about the shifter system appear on the Driver Information Center. The ignition may not release the key (on non-push-button start models).
Diagnostic Direction
The shifter module is located in the center console with the shifter mechanism. Check for power and ground at the module connector. Verify the CAN communication lines to the module. Console spill damage is a common cause of shifter module failures. The shifter mechanism itself may have internal faults that cause the module to malfunction.
Repair Considerations
If the module requires replacement, it must be programmed to the vehicle using GM diagnostic equipment. In the meantime, some vehicles allow a manual override to get out of Park for towing or service positioning. Consult your owner's manual for the specific procedure.