2021 Cadillac CT4 Technical Service Bulletins

814 technical service bulletins (TSBs) are on record for the 2021 Cadillac CT4. TSBs are notes manufacturers send to dealers about repair procedures for issues seen in the field. They are not recalls and do not by themselves mean a vehicle has a fault.

• 11015535Mar 11, 2025Other or unknown. Emissions Recall - General Motors has decided to conduct an Emission Recall involving certain 2021 Cadillac CT4 and CT5 vehicles with a 2.0L engine. The Engine Control Module (ECM) may not properly diagnose, may not set Diagnostic Trouble Codes (DTCs) or may not illuminate the Malfunction Indicator Light (Check Engine Light) if certain fault conditions of the catalytic converter were to occur.
• 11015336Mar 7, 2025Transmission and drivetrain. Certain vehicles listed above, may have a condition where the transmission control valve has worn, resulting in a gradual loss of pressure within the valve. The effects can cause harsh shifting, setting a service engine soon message, reduced engine performance or P0747 diagnostic trouble code.
• 11015573Mar 5, 2025Engine, Electrical system. This service bulletin provides repair information to correct a customer concern of a loss of cabin heat.
• 11015567Mar 5, 2025Other or unknown. This warranty administration bulletin provides information regarding the field action courtesy transportation policy.
• 11016942Mar 4, 2025Engine. This bulletin advises the technician to flush the cooling system multiple times if oil has been found in the cooling system and replace the parts that may be contaminated due to oil in system.
• 11015577Mar 3, 2025Engine, Steering. This Preliminary information communicates to the technicians some additional diagnostic steps to perform if they encounter a no crank condition and/or loss of power steering.
• 11014622Mar 2, 2025Transmission and drivetrain. This Preliminary information communicates Diagnostic aids for a no start or DTC'S following a transmission replacement
• 11014621Mar 2, 2025Transmission and drivetrain. This Preliminary information communicates Diagnostic aids for a no start or DTC'S following a transmission replacement
• 11015409Feb 25, 2025Wheels, Suspension. This service bulletin provides information on Wheel Alignment Specifications, Requirements and Recommendations for GM Vehicles.
• 11015387Feb 22, 2025Other or unknown. This Warranty Administration bulletin provides information on Dealer Empowerment for Goodwill, Customer Enthusiasm and Policy (U.S. Only).
• 11015382Feb 20, 2025Body and structure. This informational bulletin provides a procedure on how to remove the paint stain that may present itself under the shipping film.
• 11014455Feb 20, 2025Other or unknown. This Preliminary Information communication provides information to the technician about vehicles that have an unusual noise and is difficult to identify, isolate or pinpoint. Technician should get record a sound clip or take a video of the noise for assessment by engineering. Technician will need to call General Motors Technical Assistance Center for further assistance.
• 11014577Feb 18, 2025Steering. This service bulletin provides a procedure inspecting for excess grease or Sealant on the Exterior of the steering gear due to seeing grease or sealant on certain locations on the gear.
• 11014450Feb 18, 2025Other or unknown. This Preliminary information communicates a "Forward Collision System Reduced" message displayed on the DIC when the Forward Automatic Braking has been set to the "Alert" setting. This is normal when the FAB has been set to "Alert".
• 11014565Feb 13, 2025Transmission and drivetrain. This bulletin helps aid the tech in possible noise that may be normal or abnormal depending on the concern noted.
• 11014563Feb 13, 2025Other or unknown. This warranty administration bulletin provides policy information for GM courtesy transportation and roadside assistance programs.
• 11014353Feb 12, 2025Transmission and drivetrain. This service bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
• 11014230Jan 31, 2025Wheels, Electrical system, Engine, Visibility (wipers, defrost, mirrors), Brakes. This bulletin advises the dealers to maintain the vehicle stock on hand by doing a full inspection on the vehicles before being sold (prepping) to the customer.
• 11014171Jan 31, 2025Body and structure, Vehicle speed control. This service bulletin provides information on proper use of floor mats.
• 11014238Jan 30, 2025Body and structure, Other or unknown. This warranty administration service bulletin provides information about GM Accessories - Dealer-Installed, Repaired or Replaced During Warranty Coverage Period.
• 11014233Jan 30, 2025Engine. 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.
• 11014239Jan 29, 2025Electrical system, Other or unknown. This service bulletin provides information on the Transport Mode Feature, also known as Logistics mode, which is used to increase the 12V Battery stand time of the vehicle during transit and or long period of stand time at the dealerships.
• 11013227Jan 29, 2025Other or unknown. Service Update. Certain vehicles equipped with a 2.7L engine (RPO L3B), may have an Engine Control Module (ECM) that does not sufficiently control fuel injector flow rate under certain driving conditions. Dealers are to reprogram the ECM.
• 11014222Jan 28, 2025Electrical system, Other or unknown. This service bulletin provides information to inform dealership personnel about Law Enforcement and Government vehicles that request to disable or enable content.
• 11014170Jan 27, 2025Exterior lighting. This service bulletin provides information on Exterior Lamp Condensation and Water Leak Information and Replacement Guidelines.
• 11013468Jan 24, 2025Other or unknown. This Preliminary information communicates a diagnostic tip on how to resolve a issue if the serial data authentication configuration did not complete correctly.
• 11013463Jan 24, 2025Other or unknown. This Preliminary information communicates diagnostic tips on how to resolve a issues with vehicles that will not power up after a can bus 2 issue, lightning strike, or a failed over the air update.
• 11013243Jan 18, 2025Engine. This service bulletin provides diagnostic repair information to correct an oil leak in the engine.
• 11013269Jan 16, 2025Body and structure, Steering, Electrical system, Seats, Engine. This informational bulletin provides a guide on how to diagnose and test for vibrations utilizing the PicoScope.
• 11012967Jan 10, 2025Other or unknown. This Preliminary information communicates a diagnostic tip on how to resolve a issue if the serial data authentication configuration did not complete correctly.
• 11012966Jan 10, 2025Other or unknown. This Preliminary information communicates diagnostic tips on how to resolve a issues with vehicles that will not power up after a can bus 2 issue, lightning strike, or a failed over the air update.
• 11013069Jan 9, 2025Transmission and drivetrain, Electrical system, Engine. This bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.
• 11012929Jan 7, 2025Electrical system. This warranty administration bulletin provides policy information on the requirements for 12V battery testing and warranty replacements.
• 11012930Jan 4, 2025Other or unknown. This warranty administration bulletin provides policy information for GM courtesy transportation and roadside assistance programs.
• 11012908Dec 21, 2024Other or unknown. This service bulletin provides information for customers/dealers/technicians on Normal Camera Display Operation - Flashing Diamond - Spot - or UFO like image on Camera Display.
• 11012690Dec 14, 2024Other or unknown. This warranty administration bulletin provide policy information for variable diagnostic time allowances on select labor operations (U.S. Only).
• 11011885Dec 14, 2024Electrical system, Fuel system, Other or unknown. This Preliminary information communicates diagnostic tips on how to resolve a issues with vehicles that will not power up after a can bus 2 issue, lightning strike, or a failed over the air update.
• 11011872Dec 13, 2024Other or unknown, Electrical system, Engine. This Preliminary information communicates a diagnostic tip on how to resolve a issue if the serial data authentication configuration did not complete correctly.
• 11011857Dec 10, 2024Electrical system, Other or unknown. This Preliminary information communicates Diagnostic Tips When Having Difficulties Programming Or Adding Key Fobs / Transmitters.
• 11011782Dec 7, 2024Other or unknown. This Preliminary Information communication provides information to the technician about the use of J-35616-64B terminal test probe, replacement terminals, and terminated leads. The J-35616-64B is the latest test probe released for checking tension or probing the .64 series terminals. The test probe terminal has been released in the terminal repair kit (J-38125-620H) located in Lear Tray 7 part number 963716-2.
• 11012189Dec 6, 2024Electrical system. This service bulletin provides information on the Transport Mode Feature, also known as Logistics mode, which is used to increase the 12V Battery stand time of the vehicle during transit and or long period of stand time at the dealerships.
• 11012183Dec 6, 2024Engine. This service bulletin provides diagnostic repair information to correct an oil leak on top of the engine that may be coming from cam carrier- T-joint area.
• 11011805Dec 6, 2024Other or unknown, Electrical system. This Preliminary information communicates a GM part number for reflective high temperature heat or insulating tape when repairing wiring harnesses.
• 11012009Nov 27, 2024Transmission and drivetrain. This bulletin helps aid the tech in possible transmission noise that may be normal or abnormal depending on the concern noted.
• 11011993Nov 27, 2024Wheels, Air bags, Transmission and drivetrain. This service bulletin provides repair information to correct customer concerns of Wheel Lock Up, ABS Event, Loud Bang and a Flashing “D” on Driver Information Center (DIC) when Lightly or Moderately Accelerating Forcing an 8-7 or 8-6 Downshift.
• 11011989Nov 27, 2024Transmission and drivetrain. This service bulletin provides information on the harmful effects of ethylene glycol in transmission fluid.
• 11011996Nov 25, 2024Electrical system, Other or unknown. This service bulletin provides diagnostic/repair information to correct a customer concern of Cellphone not Charging or USB Receptacle Inoperative.
• 11010793Nov 25, 2024Electrical system. Customer Satisfaction Program. Certain vehicles, equipped with Super Cruise require high-definition road maps to be updated frequently. This ensures the vehicle is current with road changes and any additional Super Cruise approved mapped roads. Dealers will reprogram the automated driving mapping module and the image processing module.
• 11011900Nov 22, 2024Engine. This diagnostic tip bulletin provides additional information on how to diagnose a possible valve, lifter or camshaft issue.
• 11011337Nov 21, 2024Other or unknown. This Preliminary information communicates an issue where the odometer mileage is incorrect after performing a module setup procedure and a FSE will be dispatched to the vehicle to correct the odometer error.

← All problems reported for the 2021 Cadillac CT4