Cadillac CT4 Service Bulletins (2025)
241 manufacturer communications on file.
- October 7, 2026•Document ID: 11038460Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIT6110L
- Date Added:
- October 14, 2026
- Manufacturer:
- CADILLAC
SummaryThis Preliminary information communicates an issue with the SES MIL and DTC P062B and engineering is currently investigating.
Associated Products (84)2027 Buick Encore GX2027 Chevrolet Trailblazer2026 Buick Encore GX2026 Buick Envision2026 Cadillac CT42026 Cadillac CT52026 Cadillac Escalade2026 Cadillac Escalade ESV2026 Cadillac XT52026 Chevrolet Blazer2026 Chevrolet Colorado2026 Chevrolet Express2026 Chevrolet Silverado2026 Chevrolet Suburban2026 Chevrolet Tahoe2026 Chevrolet Trailblazer2026 GMC Canyon2026 GMC Savana2026 GMC Sierra2026 GMC Yukon+ 64 moreAssociated Documents - September 28, 2026•Document ID: 11038136Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIT6457C
- Date Added:
- October 5, 2026
- Manufacturer:
- CHEVROLET
SummaryThis preliminary information is for technicians that may see DTCs that are history and should not perform any part replacements. They should follow the notes mentioned prior to anything being replaced.
Associated Products (173)2027 Buick Enclave2027 Buick Encore GX2027 Cadillac Escalade IQ2027 Cadillac Escalade IQL2027 Cadillac Lyriq2027 Cadillac Optiq2027 Cadillac Vistiq2027 Chevrolet Blazer2027 Chevrolet Bolt EV2027 Chevrolet Corvette2027 Chevrolet Equinox2027 Chevrolet Suburban2027 Chevrolet Tahoe2027 Chevrolet Trailblazer2027 Chevrolet Traverse2027 GMC Acadia2027 GMC Sierra2027 GMC Terrain2027 GMC Yukon2027 GMC Yukon XL+ 153 moreAssociated Documents - September 28, 2026•Document ID: 11038132Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIC6540K
- Date Added:
- October 5, 2026
- Manufacturer:
- CHEVROLET
SummaryThis Preliminary information communicates to dealers a procedure to reset the radio.
Associated Products (173)2027 Buick Enclave2027 Buick Encore GX2027 Cadillac Escalade IQ2027 Cadillac Escalade IQL2027 Cadillac Lyriq2027 Cadillac Optiq2027 Cadillac Vistiq2027 Chevrolet Blazer2027 Chevrolet Bolt EV2027 Chevrolet Corvette2027 Chevrolet Equinox2027 Chevrolet Suburban2027 Chevrolet Tahoe2027 Chevrolet Trailblazer2027 Chevrolet Traverse2027 GMC Acadia2027 GMC Sierra2027 GMC Terrain2027 GMC Yukon2027 GMC Yukon XL+ 153 moreAssociated Documents - September 26, 2026•Document ID: 11037555Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIT5698F
- Date Added:
- September 30, 2026
- Manufacturer:
- CADILLAC
SummaryThis PI provides Diagnostics tips on how the LIN bus works and how to diagnosis it.
Associated Products (619)2027 Buick Enclave2027 Buick Encore GX2027 Cadillac Escalade IQ2027 Cadillac Escalade IQL2027 Cadillac Lyriq2027 Cadillac Optiq2027 Cadillac Vistiq2027 Chevrolet Blazer2027 Chevrolet Bolt EV2027 Chevrolet Corvette2027 Chevrolet Equinox2027 Chevrolet Suburban2027 Chevrolet Tahoe2027 Chevrolet Trailblazer2027 Chevrolet Traverse2027 GMC Acadia2027 GMC Sierra2027 GMC Terrain2027 GMC Yukon2027 GMC Yukon XL+ 599 moreAssociated Documents - September 10, 2026•Document ID: 11037744Over The AirUNKNOWN OR OTHER
- Mfr Comm. #:
- 663.10
- Date Added:
- October 2, 2026
- Manufacturer:
- CADILLAC
SummaryThis update contains a required software change to help improve the overall software update and diagnostics process. Be sure to install this update to be able to receive future software updates. During the update process, your radio may stay on up to 5 minutes after you exit the vehicle. This is expected behavior.
Associated Products (4)Associated Documents - September 8, 2026•Document ID: 11037319Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIC6555A
- Date Added:
- September 16, 2026
- Manufacturer:
- CADILLAC
SummaryThis PI advises of a procedure for a Service Door Latch System message with No Related DTCs
Associated Products (14)Associated Documents - September 4, 2026•Document ID: 11037253Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIP4902W
- Date Added:
- September 10, 2026
- Manufacturer:
- CHEVROLET
SummaryThis preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
Associated Products (751)2027 Buick Enclave2027 Buick Encore GX2027 Cadillac Escalade IQ2027 Cadillac Escalade IQL2027 Cadillac Lyriq2027 Cadillac Optiq2027 Cadillac Vistiq2027 Chevrolet Blazer2027 Chevrolet Bolt EV2027 Chevrolet Corvette2027 Chevrolet Equinox2027 Chevrolet Trailblazer2027 Chevrolet Traverse2027 GMC Acadia2027 GMC Terrain2026 Buick Enclave2026 Buick Encore2026 Buick Encore GX2026 Buick Envision2026 Buick Envista+ 731 moreAssociated Documents - August 27, 2026•Document ID: 11036690Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIT6541
- Date Added:
- September 2, 2026
- Manufacturer:
- GMC
SummaryThis Preliminary information communicates to the technicians a diagnostic tip if a technician loses communication with the image processor #2 and how to restore communication
Associated Products (130)2027 Buick Enclave2027 Buick Encore GX2027 Cadillac Escalade IQ2027 Cadillac Escalade IQL2027 Cadillac Lyriq2027 Cadillac Optiq2027 Cadillac Vistiq2027 Chevrolet Blazer2027 Chevrolet Bolt EV2027 Chevrolet Corvette2027 Chevrolet Equinox2027 Chevrolet Trailblazer2027 Chevrolet Traverse2027 GMC Acadia2027 GMC Terrain2026 Buick Enclave2026 Buick Encore2026 Buick Encore GX2026 Buick Envision2026 Buick Envista+ 110 moreAssociated Documents - August 20, 2026•Document ID: 11036392Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIC6551C
- Date Added:
- August 27, 2026
- Manufacturer:
- CADILLAC
SummaryThis Preliminary information communicates to dealer to perform a MEC reset for wireless projection issues
Associated Products (233)2026 Buick Enclave2026 Buick Encore2026 Buick Encore GX2026 Buick Envision2026 Buick Envista2026 Cadillac Celestiq2026 Cadillac CT42026 Cadillac CT52026 Cadillac Escalade2026 Cadillac Escalade ESV2026 Cadillac Escalade IQ2026 Cadillac Escalade IQL2026 Cadillac Lyriq2026 Cadillac Optiq2026 Cadillac Vistiq2026 Cadillac XT42026 Cadillac XT52026 Cadillac XT62026 Chevrolet Blazer2026 Chevrolet BrightDrop+ 213 moreAssociated Documents - July 28, 2026•Document ID: 11035693Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIT6110K
- Date Added:
- August 4, 2026
- Manufacturer:
- CHEVROLET
SummaryThis Preliminary information communicates an issue with the SES MIL and DTC P062B and engineering is currently investigating.
Associated Products (84)2027 Buick Encore GX2027 Chevrolet Trailblazer2026 Buick Encore GX2026 Buick Envision2026 Cadillac CT42026 Cadillac CT52026 Cadillac Escalade2026 Cadillac Escalade ESV2026 Cadillac XT52026 Chevrolet Blazer2026 Chevrolet Colorado2026 Chevrolet Express2026 Chevrolet Silverado2026 Chevrolet Suburban2026 Chevrolet Tahoe2026 Chevrolet Trailblazer2026 GMC Canyon2026 GMC Savana2026 GMC Sierra2026 GMC Yukon+ 64 moreAssociated Documents - July 24, 2026•Document ID: 11035351Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIT6446A
- Date Added:
- July 30, 2026
- Manufacturer:
- CADILLAC
SummaryThis PI Communicates information to ensure Memory Recall is enabled to ensure memory mirrors return to set position after curbview assist is used.
Associated Products (67)2026 Cadillac CT42026 Cadillac Escalade2026 Cadillac Escalade ESV2026 Cadillac Escalade IQ2026 Cadillac Lyriq2026 Chevrolet Silverado2026 Chevrolet Suburban2026 Chevrolet Tahoe2026 GMC Hummer EV Pickup2026 GMC Hummer EV SUV2026 GMC Sierra2026 GMC Yukon2026 GMC Yukon XL2025 Cadillac CT42025 Cadillac Escalade2025 Cadillac Escalade ESV2025 Cadillac Escalade IQ2025 Cadillac Lyriq2025 Chevrolet Silverado2025 Chevrolet Suburban+ 47 moreAssociated Documents - July 21, 2026•Document ID: 11035340Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIT5099J
- Date Added:
- July 29, 2026
- Manufacturer:
- CHEVROLET
SummaryPI to help diagnose A/C concern
Associated Products (505)2026 Buick Enclave2026 Buick Encore2026 Buick Encore GX2026 Buick Envision2026 Buick Envista2026 Cadillac Celestiq2026 Cadillac CT42026 Cadillac CT52026 Cadillac Escalade2026 Cadillac Escalade ESV2026 Cadillac Escalade IQ2026 Cadillac Escalade IQL2026 Cadillac Lyriq2026 Cadillac Optiq2026 Cadillac Vistiq2026 Cadillac XT42026 Cadillac XT52026 Cadillac XT62026 Chevrolet Blazer2026 Chevrolet BrightDrop+ 485 moreAssociated Documents - July 13, 2026•Document ID: 11035299Over The AirUNKNOWN OR OTHER
- Mfr Comm. #:
- 662.30
- Date Added:
- July 29, 2026
- Manufacturer:
- CADILLAC
Summary• Improvements to system responsiveness • Improvements to camera image clarity • Fixes to prevent blank screens and audio drop-outs • Improvements to vehicle software update installation
Associated Products (4)Associated Documents - July 7, 2026•Document ID: 11034068Over The AirUNKNOWN OR OTHER
- Mfr Comm. #:
- 662.20
- Date Added:
- June 26, 2026
- Manufacturer:
- CADILLAC
Summary• Improves transmission diagnostic software. • Reduces unnecessary check
Associated Products (4)Associated Documents - June 23, 2026•Document ID: 11034769Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIT5966F
- Date Added:
- July 7, 2026
- Manufacturer:
- CHEVROLET
SummaryThis Preliminary information communicates an issue with an OTA pending message still displayed after an OTA event and how to reset/clear the message.
Associated Products (232)2026 Buick Enclave2026 Buick Encore2026 Buick Encore GX2026 Buick Envision2026 Buick Envista2026 Cadillac Celestiq2026 Cadillac CT42026 Cadillac CT52026 Cadillac Escalade2026 Cadillac Escalade ESV2026 Cadillac Escalade IQ2026 Cadillac Escalade IQL2026 Cadillac Lyriq2026 Cadillac Optiq2026 Cadillac Vistiq2026 Cadillac XT42026 Cadillac XT52026 Cadillac XT62026 Chevrolet Blazer2026 Chevrolet BrightDrop+ 212 moreAssociated Documents - June 18, 2026•Document ID: 11034066Over The AirUNKNOWN OR OTHER
- Mfr Comm. #:
- 661.20
- Date Added:
- June 26, 2026
- Manufacturer:
- CADILLAC
Summary• Improves traction and stability control when accelerating or on uneven terrain. • Improves braking and stopping performance on low-traction surfaces. • Improves the performance of assisted braking features. • The active cabin ventilation feature will operate more reliably. • Additional protection for the health of your battery and updates to help prevent excessive battery drain and overheating. • Improvements will support successful software updates for your vehicle and allow you to access new features and fixes.
Associated Products (2)Associated Documents - June 16, 2026•Document ID: 11034038Over The AirUNKNOWN OR OTHER
- Mfr Comm. #:
- N25-252332
- Date Added:
- June 24, 2026
- Manufacturer:
- GMC
Summary• Fixes to help prevent loss of functionality for connectivity features such as OnStar, Wi-Fi, Navigation, and Super Cruise.
Associated Products (35)2026 Buick Enclave2026 Buick Envision2026 Cadillac Celestiq2026 Cadillac CT42026 Cadillac CT52026 Cadillac Lyriq2026 Cadillac Optiq2026 Chevrolet Blazer2026 Chevrolet Corvette2026 Chevrolet Equinox2026 Chevrolet Silverado2026 Chevrolet Traverse2026 GMC Acadia2026 GMC Sierra2026 GMC Terrain2025 Buick Enclave2025 Cadillac Celestiq2025 Cadillac CT42025 Cadillac CT52025 Cadillac Lyriq+ 15 moreAssociated Documents - June 3, 2026•Document ID: 11033726Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIT6503A
- Date Added:
- June 8, 2026
- Manufacturer:
- CHEVROLET
SummaryThis preliminary information is to inform technicians that GM is placing the B174W Front View Camera Module (ACP2) on part restriction due to elevated replacement rates and ongoing engineering investigation. Technicians must not replace the front camera module unless they have: 1.Completed the diagnostic procedure in this PI, and 2.Contacted TAC and received authorization, including the SI document number and specific step that directs camera replacement.
Associated Products (114)2026 Buick Enclave2026 Buick Encore2026 Buick Encore GX2026 Buick Envision2026 Buick Envista2026 Cadillac Celestiq2026 Cadillac CT42026 Cadillac CT52026 Cadillac Escalade2026 Cadillac Escalade ESV2026 Cadillac Escalade IQ2026 Cadillac Escalade IQL2026 Cadillac Lyriq2026 Cadillac Optiq2026 Cadillac Vistiq2026 Cadillac XT42026 Cadillac XT52026 Cadillac XT62026 Chevrolet Blazer2026 Chevrolet BrightDrop+ 94 moreAssociated Documents - May 27, 2026•Document ID: 11033150Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIT6519
- Date Added:
- June 2, 2026
- Manufacturer:
- CHEVROLET
SummaryThis preliminary information is to inform technicians and customers that the voice command will be inoperative when trying to open applications. Engineering is investigating and this PI will be converted to a bulletin when a repair is available.
Associated Products (170)2027 Chevrolet Bolt EV2027 Chevrolet Corvette2026 Buick Enclave2026 Buick Encore2026 Buick Encore GX2026 Buick Envision2026 Cadillac Celestiq2026 Cadillac CT42026 Cadillac CT52026 Cadillac Escalade2026 Cadillac Escalade ESV2026 Cadillac Escalade IQ2026 Cadillac Escalade IQL2026 Cadillac Lyriq2026 Cadillac Optiq2026 Cadillac XT42026 Cadillac XT52026 Cadillac XT62026 Chevrolet Blazer2026 Chevrolet BrightDrop+ 150 moreAssociated Documents - May 21, 2026•Document ID: 11032955Service Bulletin/Repair InstructionsUNKNOWN OR OTHER
- Mfr Comm. #:
- PIP6115
- Date Added:
- May 28, 2026
- Manufacturer:
- CHEVROLET
SummaryThe document advise technicians after an engine repair involving removal of the camshaft actuators, the vehicle may set p1101 P0172 and or stalls when taken off idle. The technician is instructed to verify the intake and exhaust camshaft actuators are installed onto the correct camshafts.
Associated Products (31)2026 Cadillac CT42026 Chevrolet Colorado2026 Chevrolet Silverado2026 GMC Canyon2026 GMC Sierra2025 Cadillac CT42025 Chevrolet Colorado2025 Chevrolet Silverado2025 GMC Canyon2025 GMC Sierra2024 Cadillac CT42024 Chevrolet Colorado2024 Chevrolet Silverado2024 GMC Canyon2024 GMC Sierra2023 Cadillac CT42023 Chevrolet Colorado2023 Chevrolet Silverado2023 GMC Canyon2023 GMC Sierra+ 11 moreAssociated Documents