Cadillac XT4 Service Bulletins (2021)

685 manufacturer communications on file.

• September 26, 2026•Document ID: 11037555

  Service Bulletin/Repair Instructions
  UNKNOWN OR OTHER

  Mfr Comm. #:

  PIT5698F

  Date Added:

  September 30, 2026

  Manufacturer:

  CADILLAC

  Summary

  This PI provides Diagnostics tips on how the LIN bus works and how to diagnosis it.

  Associated Products (619)

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  Associated Documents

  • DownloadMC-11037555-0001.pdf↗
• September 4, 2026•Document ID: 11037253

  Service Bulletin/Repair Instructions
  UNKNOWN OR OTHER

  Mfr Comm. #:

  PIP4902W

  Date Added:

  September 10, 2026

  Manufacturer:

  CHEVROLET

  Summary

  This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.

  Associated Products (751)

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  Associated Documents

  • DownloadMC-11037253-0001.pdf↗
• August 20, 2026•Document ID: 11036392

  Service Bulletin/Repair Instructions
  UNKNOWN OR OTHER

  Mfr Comm. #:

  PIC6551C

  Date Added:

  August 27, 2026

  Manufacturer:

  CADILLAC

  Summary

  This Preliminary information communicates to dealer to perform a MEC reset for wireless projection issues

  Associated Products (233)

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  Associated Documents

  • DownloadMC-11036392-0001.pdf↗
• July 21, 2026•Document ID: 11035340

  Service Bulletin/Repair Instructions
  UNKNOWN OR OTHER

  Mfr Comm. #:

  PIT5099J

  Date Added:

  July 29, 2026

  Manufacturer:

  CHEVROLET

  Summary

  PI to help diagnose A/C concern

  Associated Products (505)

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  Associated Documents

  • DownloadMC-11035340-0001.pdf↗
• June 23, 2026•Document ID: 11034769

  Service Bulletin/Repair Instructions
  UNKNOWN OR OTHER

  Mfr Comm. #:

  PIT5966F

  Date Added:

  July 7, 2026

  Manufacturer:

  CHEVROLET

  Summary

  This 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)

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  Associated Documents

  • DownloadMC-11034769-0001.pdf↗
• May 11, 2026•Document ID: 11032764

  Service Bulletin/Repair Instructions
  UNKNOWN OR OTHER

  Mfr Comm. #:

  PIC6423A

  Date Added:

  May 19, 2026

  Manufacturer:

  BUICK

  Summary

  Pi created to provide GM dealers with information on gathering information for projection issue

  Associated Products (232)

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  Associated Documents

  • DownloadMC-11032764-0001.pdf↗
• May 11, 2026•Document ID: 11032763

  Service Bulletin/Repair Instructions
  UNKNOWN OR OTHER

  Mfr Comm. #:

  PIC6551B

  Date Added:

  May 19, 2026

  Manufacturer:

  CADILLAC

  Summary

  This Preliminary information communicates to dealer to perform a MEC reset for wireless projection issues

  Associated Products (232)

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  Associated Documents

  • DownloadMC-11032763-0001.pdf↗
• April 1, 2026•Document ID: 11030974

  Service Bulletin/Repair Instructions
  UNKNOWN OR OTHER

  Mfr Comm. #:

  PIT3271Q

  Date Added:

  April 7, 2026

  Manufacturer:

  CADILLAC

  Summary

  This preliminary information communicates information about how to determine if a wheel and tires size change is available.

  Associated Products (736)

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  Associated Documents

  • DownloadMC-11030974-0001.pdf↗
• March 27, 2026•Document ID: 11030360

  Service Bulletin/Repair Instructions
  UNKNOWN OR OTHER

  Mfr Comm. #:

  PIT5992B

  Date Added:

  March 31, 2026

  Manufacturer:

  CHEVROLET

  Summary

  This preliminary information discusses a condition that may arise from the drivers window switch sending an errant message causing the vehicle to enter manual fob learn mode.

  Associated Products (19)

  2024 Chevrolet Equinox2024 GMC Terrain2023 Cadillac XT42023 Chevrolet Equinox2023 GMC Terrain2022 Cadillac XT42022 Chevrolet Equinox2022 GMC Terrain2021 Cadillac XT42021 Chevrolet Equinox2021 GMC Terrain2020 Cadillac XT42020 Chevrolet Equinox2020 GMC Terrain2019 Cadillac XT42019 Chevrolet Equinox2019 GMC Terrain2018 Chevrolet Equinox2018 GMC Terrain
  Associated Documents

  • DownloadMC-11030360-0001.pdf↗
• March 21, 2026•Document ID: 11030532

  Over The Air
  UNKNOWN OR OTHER

  Mfr Comm. #:

  N25-250552

  Date Added:

  April 2, 2026

  Manufacturer:

  CHEVROLET

  Summary

  Improvements to OnStar functionality.

  Associated Products (47)

  2023 Buick Enclave2023 Buick Encore2023 Cadillac XT42023 Cadillac XT52023 Cadillac XT62023 Chevrolet Blazer2023 Chevrolet Bolt EUV2023 Chevrolet Bolt EV2023 Chevrolet Camaro2023 Chevrolet Equinox2023 Chevrolet Malibu2023 Chevrolet Silverado2023 Chevrolet Trailblazer2023 GMC Acadia2023 GMC Sierra2023 GMC Terrain2022 Buick Enclave2022 Buick Encore2022 Cadillac XT42022 Cadillac XT5+ 27 more
  Associated Documents

  • DownloadMC-11030532-0001.pdf↗
• March 9, 2026•Document ID: 11030092

  Service Bulletin/Repair Instructions
  UNKNOWN OR OTHER

  Mfr Comm. #:

  PIP6104

  Date Added:

  March 17, 2026

  Manufacturer:

  CHEVROLET

  Summary

  This Preliminary information communicates the steps on how to save a GDS2 Session Log and upload to a Technical Assistance Case in CX Connect.

  Associated Products (736)

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  Associated Documents

  • DownloadMC-11030092-0001.pdf↗
• March 9, 2026•Document ID: 11030091

  Service Bulletin/Repair Instructions
  UNKNOWN OR OTHER

  Mfr Comm. #:

  PIP4902V

  Date Added:

  March 17, 2026

  Manufacturer:

  BUICK

  Summary

  This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.

  Associated Products (736)

  2027 Chevrolet Bolt EV2026 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 Blazer+ 716 more
  Associated Documents

  • DownloadMC-11030091-0001.pdf↗
• March 2, 2026•Document ID: 11029950

  Service Bulletin/Repair Instructions
  UNKNOWN OR OTHER

  Mfr Comm. #:

  PIT6425D

  Date Added:

  March 11, 2026

  Manufacturer:

  CADILLAC

  Summary

  This Preliminary information communicates to the field on how to diagnosis a GPS issue with the Telematic module with no DTC'ss

  Associated Products (325)

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  Associated Documents

  • DownloadMC-11029950-0001.pdf↗
• February 19, 2026•Document ID: 11028909

  Emissions
  FUEL/PROPULSION SYSTEM

  Mfr Comm. #:

  N252516900-01

  Date Added:

  February 19, 2026

  Manufacturer:

  GMC

  Summary

  Emission Recall. General Motors has decided to conduct a Voluntary Emission Recall. Certain vehicles listed above may have a condition which can cause the fuel pump power control module to fail. If this were to occur, fuel flow to the engine could be interrupted. Dealers will replace the fuel pump power control module.

  Associated Products (23)

  2023 Cadillac XT42022 Buick Envision2022 Cadillac XT42022 Cadillac XT52022 Cadillac XT62022 Chevrolet Equinox2022 GMC Acadia2022 GMC Terrain2021 Buick Envision2021 Cadillac Escalade2021 Cadillac Escalade ESV2021 Cadillac XT42021 Cadillac XT52021 Cadillac XT62021 Chevrolet Blazer2021 Chevrolet Camaro2021 Chevrolet Malibu2021 Chevrolet Suburban2021 Chevrolet Tahoe2021 GMC Acadia+ 3 more
  Associated Documents

  • DownloadMC-11028909-0001.pdf↗
• February 5, 2026•Document ID: 11028977

  Over The Air
  UNKNOWN OR OTHER

  Mfr Comm. #:

  N25-250552

  Date Added:

  February 24, 2026

  Manufacturer:

  GMC

  Summary

  Improvements to OnStar functionality. During the update process, your radio may stay on up to 5 minutes after you exit the vehicle. This is expected behavior when an update package is onboard the vehicle. Do not service your vehicle during installation.

  Associated Products (33)

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  Associated Documents

  • DownloadMC-11028977-0001.pdf↗
• February 5, 2026•Document ID: 11028382

  Emissions
  FUEL/PROPULSION SYSTEM

  Mfr Comm. #:

  N252516900

  Date Added:

  February 5, 2026

  Manufacturer:

  GMC

  Summary

  Emission Recall. Additional VINs moved to Open status.

  Associated Products (23)

  2023 Cadillac XT42022 Buick Envision2022 Cadillac XT42022 Cadillac XT52022 Cadillac XT62022 Chevrolet Equinox2022 GMC Acadia2022 GMC Terrain2021 Buick Envision2021 Cadillac Escalade2021 Cadillac Escalade ESV2021 Cadillac XT42021 Cadillac XT52021 Cadillac XT62021 Chevrolet Blazer2021 Chevrolet Camaro2021 Chevrolet Malibu2021 Chevrolet Suburban2021 Chevrolet Tahoe2021 GMC Acadia+ 3 more
  Associated Documents

  • DownloadMC-11028382-0001.pdf↗
• February 4, 2026•Document ID: 11028658

  Service Bulletin/Repair Instructions
  UNKNOWN OR OTHER

  Mfr Comm. #:

  PIP5841H

  Date Added:

  February 9, 2026

  Manufacturer:

  BUICK

  Summary

  This Preliminary information communicates the potential for condensation to freeze up inside the Crankcase Pressure Sensor causing dtc P04FB to set.

  Associated Products (47)

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  Associated Documents

  • DownloadMC-11028658-0001.pdf↗
• January 29, 2026•Document ID: 11027870

  Emissions
  FUEL/PROPULSION SYSTEM

  Mfr Comm. #:

  N252516900

  Date Added:

  January 29, 2026

  Manufacturer:

  CHEVROLET

  Summary

  Emission Recall. Additional VINs Moved to ‘Open’ Status

  Associated Products (23)

  2023 Cadillac XT42022 Buick Envision2022 Cadillac XT42022 Cadillac XT52022 Cadillac XT62022 Chevrolet Equinox2022 GMC Acadia2022 GMC Terrain2021 Buick Envision2021 Cadillac Escalade2021 Cadillac Escalade ESV2021 Cadillac XT42021 Cadillac XT52021 Cadillac XT62021 Chevrolet Blazer2021 Chevrolet Camaro2021 Chevrolet Malibu2021 Chevrolet Suburban2021 Chevrolet Tahoe2021 GMC Acadia+ 3 more
  Associated Documents

  • DownloadMC-11027870-0001.pdf↗
• January 16, 2026•Document ID: 11027697

  Service Bulletin/Repair Instructions
  UNKNOWN OR OTHER

  Mfr Comm. #:

  PIT6425C

  Date Added:

  January 19, 2026

  Manufacturer:

  BUICK

  Summary

  This Preliminary information communicates to the field on how to diagnosis a GPS issue with the Telematic module with no DTC's

  Associated Products (325)

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  Associated Documents

  • DownloadMC-11027697-0001.pdf↗
• January 15, 2026•Document ID: 11027666

  Emissions
  FUEL/PROPULSION SYSTEM

  Mfr Comm. #:

  N252516900

  Date Added:

  January 15, 2026

  Manufacturer:

  GMC

  Summary

  Emission Recall. Fuel Pump Power Control Module. Additional VINs Moved to ‘Open’ Status

  Associated Products (23)

  2023 Cadillac XT42022 Buick Envision2022 Cadillac XT42022 Cadillac XT52022 Cadillac XT62022 GMC Acadia2022 GMC Terrain2021 Buick Envision2021 Cadillac Escalade2021 Cadillac Escalade ESV2021 Cadillac XT42021 Cadillac XT52021 Cadillac XT62021 Chevrolet Blazer2021 Chevrolet Camaro2021 Chevrolet Equinox2021 Chevrolet Malibu2021 Chevrolet Suburban2021 Chevrolet Tahoe2021 GMC Acadia+ 3 more
  Associated Documents

  • DownloadMC-11027666-0001.pdf↗