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Service bulletins for the 2020 Cadillac CT4

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.

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

By type

By component

By trouble code

By topic

Bulletins, newest first
PIP4902Q2023-01-30. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Preliminary Information communication provides information to the technician that General Motors Technical Assistance Center may ask for Global Diagnostic System 2 Session Log. Technician will need use Global Diagnostic System 2 to send the session logs to General Motors Technical Assistance Center for further assistance on the vehicle in question.
21-NA-1352023-01-25. Service bulletin. ELECTRICAL SYSTEM. This service bulletin provides information to inform dealership personnel about Law Enforcement and Government vehicles that request to disable or enable content.
22-NA-1152023-01-25. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. This service bulletin provides information for U.S. dealers ONLY to refer to the Battery Maintenance Report to identify vehicles in dealer inventory that require attention.
20-NA-0182023-01-25. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This service bulletin provides information for dealers/technicians on MDI 2 Required When Programming Vehicles with Vehicle Intelligence Platform (VIP).
22-NA-2572023-01-06. Service bulletin. WHEELS. This service bulletin provides information on Dealer Installed LPO Wheel Installation and Return Process.
09-00-89-008F2023-01-06. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Warranty Administration bulletin provides retail and wholesale service personnel with the policies/procedures and the warranty transaction submission procedures that support the Personal Property Damage process.
21-NA-1242023-01-06. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin provides diagnostic tips/steps on testing for possible EVAP leaks in the system to correct a customer concern of an MIL Illuminated with DTCs P0442 and/or P0455 Set.
18-NA-0732023-01-06. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin provides graphics, information and guidelines for engine component wear to assist service personnel as a guideline to perform necessary engine repairs and prevent unnecessary engine replacement.
16-NA-3382023-01-05. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This Warranty Admin service bulletin provides guidelines for Dealers Not Required and for Dealers Required to Contact the PQC for engine or transmission assembly replacement and explains the PQC process, GWM Transaction submission, vehicle service record retention and proper handling of assembly returns for Canadian Dealers only.
22-NA-2472022-12-24. Service bulletin. SERVICE BRAKES, HYDRAULIC. This service bulletin provides information to dealership personnel that after performing a brake inspection, brake pad replacement, or any other repair that requires the caliper piston to be reseated may be causing DTC C05B0 to falsely set for eBoost applications.
22-NA-2462022-12-23. Service bulletin. POWER TRAIN. This service bulletin advises the technician that the possible cause may not be from a faulty clutch piston or extension housing and to perform testing on transmission for possible other issues, but it still may be possible on high mile vehicles that orifices in housing may have come dislodged, causing the same customer concern.
22-NA-2442022-12-21. Service bulletin. EQUIPMENT. This service bulletin provides information about GM Accessories - Dealer-Installed, Repaired or Replaced During Warranty Coverage Period.
PIT5851C2022-12-12. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Preliminary information communicates an issues with the odometer being incorrect after a programming event and how the dealership can resolve the issue.
PIT3271N2022-12-12. Service bulletin. WHEELS; TIRES. This Preliminary Information communication provides information to the technician about changing the tire and wheel size on vehicles. General Motors will only support a tire calibration for tires that have been sized, tested and designed for the vehicle in question and its applications. Technician should not use the information that is provided by the antilock braking system tire size selection.
PIT5832D2022-12-12. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE. This Preliminary information communicates a diagnostic tip on how to resolve a issue if the serial data authentication configuration did not complete correctly.
PIT5851B2022-12-12. Service bulletin. ELECTRICAL SYSTEM:INSTRUMENT PANEL:SPEEDOMETER/ODOMETER. This Preliminary information communicates an issues with the odometer being incorrect after a programming event and how the dealership can resolve the issue.
22-NA-2382022-12-07. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This service bulletin provides diagnostic/repair information to correct a customer concern of Cellphone not Charging or USB Receptacle Inoperative.
20-NA-1382022-12-06. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This bulletin provides information on Policies Applicable to All U.S. Dealers for Engine and Transmission Assembly Replacement Under Warranty, Policy or Customer Enthusiasm and information on Submission of Warranty Transaction in Global Warranty Management.
22-NA-0742022-12-03. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin provides service information to technicians on guidelines to replace Oil Cooler, Oil Cooler Lines and Oil Tank if the engine was replaced where large amounts of debris has flowed throughout the oiling system.
PIC6395C2022-11-21. Service bulletin. POWER TRAIN. This Preliminary information communicates a parts restriction is in place for the Automatic Transmission Control on 2020 Cadillac CT4, and CT5.
PIT59462022-11-21. Service bulletin. STRUCTURE; ELECTRICAL SYSTEM. This Preliminary information communicates a diagnostic tip on how to resolve a issue with the Body Control Module setting DTC: P0606 and turning on a Check Engine Lamp.
22-NA-2142022-11-03. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. This service bulletin provides a procedure to repair a customer concern of Stop/Start System Inhibited / IBS / Battery Monitor with Module Malfunction Indicator Light (MIL) Illuminated - DTC U152D, P15FF, P305D, P305E, U01B0 Set.
22-NA-2052022-11-02. Service bulletin. ELECTRICAL SYSTEM. This service bulletin provides information on Module Harvesting.
21-NA-2442022-11-02. Service bulletin. ENGINE AND ENGINE COOLING; EQUIPMENT; ELECTRICAL SYSTEM. This service bulletin provides a repair procedure to correct a customer concern of a No Fob detected message on Driver Information Center (DIC) and/or No Crank / No Start condition.
22-NA-0282022-11-02. Service bulletin. WHEELS; POWER TRAIN. This service bulletin provides a repair procedure to correct a customer concern of a Whining/Whirring, Whistle, Squeaking, Groaning/Growling Noise Coming from Front Wheel/Engine Area.

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