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B3935 on the 2021 Cadillac XT5

The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.

This code is specific to a manufacturer and is not described here. Its meaning is in the manufacturer's service information.

Bulletins for this model year that name B3935
PIC5650M2025-08-12. Service bulletin. This Preliminary Information communication provides information to the technician about vehicles that have an intermittent no crank, no start, or start stall concern with the security light coming on. Technician may find Diagnostic Trouble Codes B3055, B3060, B3935, C0750, C0755, C0760, C0765, and/or C0775.
PIC5650L2024-09-06. Service bulletin. This Preliminary Information communication provides information to the technician about vehicles that have an intermittent no crank, no start, or start stall concern with the security light coming on. Technician may find Diagnostic Trouble Codes B3055, B3060, and/or B3935. Technician should not replace any parts for this concern. If unable to duplicate the concern ask if the customer uses any Radio Frequency Identification Devices when the concern is present. Dealer should also direct their customers to the appropriate section in the Owner manuals that references that the device complies.
PIC5650K2023-06-13. Service bulletin. This Preliminary Information communication provides information to the technician about vehicles that have an intermittent no crank, no start, or start stall concern with the security light coming on. Technician may find Diagnostic Trouble Codes B3055, B3060, and/or B3935. Technician should not replace any parts for this concern. If unable to duplicate the concern ask if the customer uses any Radio Frequency Identification Devices when the concern is present. Dealer should also direct their customers to the appropriate section in the Owner manuals that references that the device complies.
PIC5650J2021-09-13. Service bulletin. This Preliminary Information communication provides information to the technician about vehicles that have an intermittent no crank, no start, or start stall concern with the security light coming on. Technician may find Diagnostic Trouble Codes B3055, B3060, and/or B3935. Technician should not replace any parts for this concern. If unable to duplicate the concern ask if the customer uses any Radio Frequency Identification Devices when the concern is present. Dealer should also direct their customers to the appropriate section in the Owner manuals that references that the device complies.

4 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.