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Service bulletins for the 2026 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.

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

By type

By component

By trouble code

Bulletins, newest first
PIT6110L2026-10-14. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates an issue with the SES MIL and DTC P062B and engineering is currently investigating.
PIT6457C2026-10-05. Service bulletin. UNKNOWN OR OTHER. This 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.
PIC6540K2026-10-05. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates to dealers a procedure to reset the radio.
663.102026-10-02. Over-the-air update. UNKNOWN OR OTHER. This 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.
663.102026-10-02. Over-the-air update. UNKNOWN OR OTHER. • Fixes to help prevent loss of audio • Better connectivity for Bluetooth and CarPlay • Improved performance for vehicle software updates
PIT5698F2026-09-30. Service bulletin. UNKNOWN OR OTHER. This PI provides Diagnostics tips on how the LIN bus works and how to diagnosis it.
PIC6555A2026-09-16. Service bulletin. UNKNOWN OR OTHER. This PI advises of a procedure for a Service Door Latch System message with No Related DTCs
PIP4902W2026-09-10. Service bulletin. UNKNOWN OR OTHER. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
PIT65412026-09-02. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates to the technicians a diagnostic tip if a technician loses communication with the image processor #2 and how to restore communication
PIC6551C2026-08-27. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates to dealer to perform a MEC reset for wireless projection issues
PIT6110K2026-08-04. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates an issue with the SES MIL and DTC P062B and engineering is currently investigating.
PIT6446A2026-07-30. Service bulletin. UNKNOWN OR OTHER. This PI Communicates information to ensure Memory Recall is enabled to ensure memory mirrors return to set position after curbview assist is used.
PIT5099J2026-07-29. Service bulletin. UNKNOWN OR OTHER. PI to help diagnose A/C concern
662.302026-07-29. Over-the-air update. UNKNOWN OR OTHER. • Improvements to system responsiveness • Improvements to camera image clarity • Fixes to prevent blank screens and audio drop-outs • Improvements to vehicle software update installation
PIT5966F2026-07-07. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates an issue with an OTA pending message still displayed after an OTA event and how to reset/clear the message.
662.202026-06-26. Over-the-air update. UNKNOWN OR OTHER. • Improves transmission diagnostic software. • Reduces unnecessary check
N25-2523322026-06-24. Over-the-air update. UNKNOWN OR OTHER. • Fixes to help prevent loss of functionality for connectivity features such as OnStar, Wi-Fi, Navigation, and Super Cruise.
PIT6503A2026-06-08. Service bulletin. UNKNOWN OR OTHER. This 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.
PIT65192026-06-02. Service bulletin. UNKNOWN OR OTHER. This 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.
661.102026-05-28. Over-the-air update. UNKNOWN OR OTHER. • Improvements to traction and stability control on uneven terrain • Improvements to braking performance on low-traction surfaces • Improvements to assisted braking • Improvements to active cabin ventilation • Additional protection for the health of your battery • Updates to help prevent excessive battery drain and overheating • Improvements to the software update system
PIP61152026-05-28. Service bulletin. UNKNOWN OR OTHER. The 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.
PIT6215C2026-05-28. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates to dealership technicians that if they encounter a customer vehicle with this concern, to perform the steps listed and should be able to reprogram the module and correct this.
PIC6540J2026-05-19. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates to dealers a procedure to reset the radio.
PIP6101B2026-05-19. Service bulletin. UNKNOWN OR OTHER. The document makes technicians aware of a valvetrain tick noise that is created by one or more soft hydraulic valve lash adjusters. The soft lash adjuster concern is due to debris from the valve rocker arm, entering into the lash adjuster. The document instructs the technician to replace all of the lash adjusters and rocker arms in the entire engine if any soft lash adjusters are found.
PIT65132026-05-19. Service bulletin. UNKNOWN OR OTHER. This PI states that if SDGM DTC U3000 Sym 49 is set and no other SDGM DTCs are present, clear DTCs and reset the SDGM. Advises of how to contact PQC to authorize SDGM replacement.

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