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Service bulletins for the 2018 Cadillac CT6

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

1096 on file from NHTSA, as of 2026-10-19.

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Only bulletins with component: Electrical system are shown. Show all

Bulletins, newest first
PIC62962018-05-21. Service bulletin. ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician that when scanning a vehicle for Diagnostic Trouble Codes, may find a temporary loss of Human Machine Interface communication with Global Diagnostic System 2. Technician should not replace the Human Machine Interface for this concern, power cycling of the Human Machine Interface fuse should restore communication. Technician should be advised that the Human Machine Interface and Global Diagnostic System 2 interaction concern has been reported to engineering for root cause and correction.
15-NA-0872018-05-21. Service bulletin. ELECTRICAL SYSTEM. This technical bulletin advises the technician to rest the MIL and diagnose additional DTCs for why the code is setting and disabling the start/stop system.
18NA1382018-05-21. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.. This technical bulletin provides a procedure to replace the HMI module to correct a condition of Radio Control (ICS) Display Does Not Remain Off at Times after it Has Been Turned Off in the Radio Settings Menu due to a software concern.
18NA0392018-05-21. Service bulletin. ELECTRICAL SYSTEM. This technical bulletin provides a procedure to reprogram the memory set module to correct a condition of Personalization Selections Intermittently Missing from Comfort and Convenience Menu due to a calibration concern.
1208132001E2018-05-21. Service bulletin. ELECTRICAL SYSTEM. This informational bulletin explains to the dealer how to cover a possible customers mistake when a fuse has been blown.
18NA1002018-05-21. Service bulletin. ELECTRICAL SYSTEM. This technical bulletin provides a procedure to reprogram both the active safety control module and the IPC to correct a condition of Super Cruise Function Difficult to Engage, Inadequate Messaging, or Service Driver Assist Message Displayed with DTC U3000.49 due to a calibration concern.
PIC6272B2018-05-21. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. The Preliminary Information communication advises the technician that the Technical Assistance Center has a Parts Restriction for Drive Motor Battery and the internal parts for the new vehicle launch of the 2017 Cadillac CT6 Plug In Hybrid. The dealer technician is advised to call the GM Technical Assistance Center for further assistance.
18NA0872018-05-21. Service bulletin. ELECTRICAL SYSTEM:HORN; EQUIPMENT:ELECTRICAL. This informational bulletin provides information on Phantom Three Beeps or Horn Chirps Heard After Turning Off Vehicle and that it should be considered normal.
17NA3372018-05-21. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.. This informational bulletin provides information to the customer on the radio display "info pages" being blank and to make sure to select in the "active info pages" menu.
17NA2152018-05-21. Service bulletin. ELECTRICAL SYSTEM. This technical bulletin provides a procedure to properly reprogram an onstar module to correct a condition of Red LED, No WiFi Operation, and/or Limited OnStar® Module Functionality After OnStar Module Replacement for Another Condition.
090604026N2018-05-21. Service bulletin. ENGINE; ELECTRICAL SYSTEM:SOFTWARE. This informational bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2 9U.S. and Canada
030603004W2018-05-21. Service bulletin. ELECTRICAL SYSTEM:12V/24V/48V BATTERY; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This warranty administration bulletin provides policy information on the requirements for battery testing and warranty replacements.
18NA0392018-05-21. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; ELECTRICAL SYSTEM. This technical bulletin provides a procedure to reprogram the memory set module to correct a condition of Personalization Selections Intermittently Missing from Comfort and Convenience Menu due to a calibration concern.
17NA3412018-04-23. Service bulletin. ELECTRICAL SYSTEM. This Bulletin provides information to use when encountering a 120V Portable Charge Cord that the Customer states does not work.
150603002H2018-04-23. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM:12V/24V/48V BATTERY. This informational bulletin provides information on approved warranty part numbers for original equipment batteries
17NA2922018-04-23. Service bulletin. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL; ELECTRICAL SYSTEM:WIRING. This technical bulletin provides a procedure to inspect the wires and/or replace the Valve Rocker Arm Oil Control Valves if the DTCs listed are set.
PIC6272A2018-03-12. Service bulletin. ELECTRICAL SYSTEM:12V/24V/48V BATTERY. The Preliminary Information communication advises the technician that the Technical Assistance Center has a Parts Restriction for Drive Motor Battery and the internal parts for the new vehicle launch of the 2017 Cadillac CT6 Plug In Hybrid. The dealer technician is advised to call the GM Technical Assistance Center for further assistance.
PIC5650D2018-01-16. Service bulletin. ELECTRICAL SYSTEM. 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.
PIC5491K2018-01-16. Service bulletin. ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician about vehicles that have an OnStar system that will not power up. Technician should turn off the ignition and cancel retained accessory power. After the vehicle has powered down remove power to the OnStar module for five minutes. After the power has been removed for five minutes, if the OnStar system is working release the vehicle. If the OnStar system is still inoperative continue with published Service Information diagnostics.
17-NA-2442017-12-22. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE. This informational bulletin provides information on Information on How to Prevent Inadvertent Vehicle Starting from Key Fob or OnStar Mobile Application and where to locate the information for future use.
17-NA-2422017-12-22. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE. This informational bulletin provides to the tech the new version of SPS that will prompt warnings when trying to reprogram modules that have been already reprogrammed.
PIC6315A2017-12-14. Service bulletin. EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.; ELECTRICAL SYSTEM. This Preliminary Information communication provides information to the technician about vehicles that in the radio settings some of the vehicle personalization selections within the Comfort and Convenience menu are missing at times. Technician will need to perform a scan for Diagnostic Trouble Codes. Technician will need to follow published Service Information diagnostics if there are Diagnostic Trouble Codes present. If the concern is and intermittent this Preliminary Information communication will be updated with a repair. When the personalization selections are not missing from the Comfort and Convenience menu but they are missing from other menus such as the Climate and Air Quality, Collision/Detection Systems, and Lighting menus, refer to bulletin 17-NA-086. Memory seat adjustments may not be available tech will need to perform a Memory Seat Module replacement/programming.
PIT55992017-12-14. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; ELECTRICAL SYSTEM. This Preliminary information communicates a false setting of DTCU0121 in the FVCM due to a FVCM software anomaly. Code U0121 will set and be moved to history in the FVCM with each ignition cycle.
PIC63152017-12-14. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.. This Preliminary Information communication provides information to the technician about vehicles that in the radio settings some of the vehicle personalization selections within the Comfort and Convenience menu are missing at times. Technician will need to perform a scan for Diagnostic Trouble Codes. Technician will need to follow published Service Information diagnostics if there are Diagnostic Trouble Codes present. If the concern is and intermittent this Preliminary Information communication will be updated with a repair. When the personalization selections are not missing from the Comfort and Convenience menu but they are missing from other menus such as the Climate and Air Quality, Collision/Detection Systems, and Lighting menus, refer to bulletin 17-NA-086. Memory seat adjustments may not be available tech will need to perform a Memory Seat Module replacement/programming.
PIC3100F2017-12-14. Service bulletin. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL. This Preliminary Information communication provides information to the technician about vehicle's odometer appears to be inaccurate relative to a known distance traveled. Technician should obtain a hand-held GPS unit to test the odometer. If a hand held GPS unit is not available, the only other option is to verify the miles traveled using a surveyor's wheel or a dynamometer.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.