# 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 bulletins from NHTSA, as of 2026-10-19. - [PIT5698F](/bulletins/11037555.md), 2026-09-30, Service bulletin: UNKNOWN OR OTHER. This PI provides Diagnostics tips on how the LIN bus works and how to diagnosis it. - [PIP5700H](/bulletins/11037550.md), 2026-09-29, Service bulletin: UNKNOWN OR OTHER. This PI communicates the proper part numbers for transmission connectors and internal harness to prevent confusion when ordering - [PIC6555A](/bulletins/11037319.md), 2026-09-16, Service bulletin: UNKNOWN OR OTHER. This PI advises of a procedure for a Service Door Latch System message with No Related DTCs - [PIP4902W](/bulletins/11037253.md), 2026-09-10, Service bulletin: UNKNOWN OR OTHER. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance. - [PIT6446A](/bulletins/11035351.md), 2026-07-30, 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. - [PIT5099J](/bulletins/11035340.md), 2026-07-29, Service bulletin: UNKNOWN OR OTHER. PI to help diagnose A/C concern - [PIP6115](/bulletins/11032955.md), 2026-05-28, 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. - [PIT6215C](/bulletins/11032952.md), 2026-05-28, 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. - [PIT6511](/bulletins/11031948.md), 2026-05-02, Service bulletin: UNKNOWN OR OTHER. This Preliminary information communicates an issue with a replace or low FOB battery message - [PIT3271Q](/bulletins/11030974.md), 2026-04-07, Service bulletin: UNKNOWN OR OTHER. This preliminary information communicates information about how to determine if a wheel and tires size change is available. - [PIP6104](/bulletins/11030092.md), 2026-03-17, Service bulletin: UNKNOWN OR OTHER. This Preliminary information communicates the steps on how to save a GDS2 Session Log and upload to a Technical Assistance Case in CX Connect. - [PIP4902V](/bulletins/11030091.md), 2026-03-17, Service bulletin: UNKNOWN OR OTHER. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance. - [PIT6425D](/bulletins/11029950.md), 2026-03-11, Service bulletin: UNKNOWN OR OTHER. This Preliminary information communicates to the field on how to diagnosis a GPS issue with the Telematic module with no DTC'ss - [PIP5865L](/bulletins/11028859.md), 2026-02-18, Service bulletin: UNKNOWN OR OTHER. This Preliminary information communicates the possibility of DTC P30BF failing on low mile vehicles due to the possibility of the cylinder 1/2 sliding barrel binding on intake camshaft. - [PIP5841H](/bulletins/11028658.md), 2026-02-09, Service bulletin: UNKNOWN OR OTHER. This Preliminary information communicates the potential for condensation to freeze up inside the Crankcase Pressure Sensor causing dtc P04FB to set. - [PIP5921B](/bulletins/11027949.md), 2026-02-01, Service bulletin: UNKNOWN OR OTHER. This Preliminary information communicates the possibility of DTC p0011 p0016 and potential for a rattle or ticking noise to occur from the Intake Cam Actuator, or cover plate screws backing out and making contact with Cam carrier - [PIP5865K](/bulletins/11027942.md), 2026-02-01, Service bulletin: UNKNOWN OR OTHER. This Preliminary information communicates the possibility of DTC P30BF failing on low mile vehicles due to the possibility of the cylinder 1/2 sliding barrel binding on intake camshaft. - [PIT5985K](/bulletins/11027932.md), 2026-02-01, Service bulletin: UNKNOWN OR OTHER. This PI provides diagnostics tips to dealership techs when trying to diagnose a CAN Bus communication issue after an event like a lightning strike, battery jump started backwards, failure over the air update, etc. - [PIP6098](/bulletins/11027701.md), 2026-01-19, Service bulletin: UNKNOWN OR OTHER. This PI advised dealer technicians of possible causes of diesel fuel contamination in gasoline powered vehicles and advises of warranty direction. - [PIT6425C](/bulletins/11027697.md), 2026-01-19, Service bulletin: UNKNOWN OR OTHER. This Preliminary information communicates to the field on how to diagnosis a GPS issue with the Telematic module with no DTC's - [PIP5700G](/bulletins/11027689.md), 2026-01-19, Service bulletin: UNKNOWN OR OTHER. This PI communicates the proper part numbers for transmission connectors and internal harness to prevent confusion when ordering - [PIP5841G](/bulletins/11027617.md), 2026-01-14, Service bulletin: UNKNOWN OR OTHER. This Preliminary information communicates the potential for condensation to freeze up inside the Crankcase Pressure Sensor causing dtc P04FB to set. - [PIP4902U](/bulletins/11027601.md), 2026-01-13, Service bulletin: UNKNOWN OR OTHER. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance. - [PIP6093](/bulletins/11026720.md), 2025-12-22, Service bulletin: UNKNOWN OR OTHER. This Preliminary information communicates the potential for condensation to freeze up inside the Crankcase Pressure Sensor causing dtc P04FB to set. - [25\-NA\-156](/bulletins/11026104.md), 2025-12-04, Service bulletin: WHEELS. This service bulletin provides information on Tire Sidewall Irregularities. More: [the next page](/v1/vehicles/2020_cadillac_ct4/bulletins?cursor=2025-12-04_11026104) (JSON) JSON: [/v1/vehicles/2020_cadillac_ct4/bulletins](/v1/vehicles/2020_cadillac_ct4/bulletins) [Report an error on this page](https://github.com/wenmar-pro/wenmar-open/issues/new?template=data_correction.yml&title=Data%20correction%3A%202020%20Cadillac%20CT4&page=https%3A%2F%2Fopen.wenmarpro.com%2Fmakes%2Fcadillac%2Fct4%2F2020%2Fbulletins&vehicle=2020%20Cadillac%20CT4)