Cadillac XT4 check engine light comes on

Filed Jul 3, 2026 · Electrical, Engine · WI

I took my suv in for diagnostics to a certified GM dealership at least twice while still under warranty. The check engine light was on, the car was behaving abnormally as well as making unusual concerning noises. The dealership sent me away saying no codes showed up and they couldn’t find a problem.The light would come on and off sporadically. I took screen shots of my dashboard every time the light came on. Within months of my warranty expiring xI was traveling to IL 1.5 hours from home on I-90 during heavy traffic. Suddenly the dashboard provided extensive messages ex: engine overheating, idle engine, etc and I could not get the rpm’s over 68, then 65; then 60; then 58 etc. I pulled over to let the engine cool on the side of a four lane bumper to bumper interstate environment alone. I had to have the car towed back from Elgin on my dime and took it into the same dealership where this time I spent 1700 on what I recall being told “engine coolant repair” as they claim small leak. Less than a month later the check engine light came back on so I took it back to the dealership. My Cadillac app was registering the same alertmas before the fix : engine coolant system. Dealership said it was a blown head gasket (something about cyl 1) sep from what they worked on for the 1700 and ate wanting over 3700 for this repair. My car was I believe months out of manufacturer warranty though I complained multiple times of concerns and because it is a “separate” issue from May repair and no year warranty from them either . 7 day wait for replacement part alone. I had car towed directly from dealership it was at to a mom n pop auto repair center in town awaiting full diagnostics, preserving “evidence” I learned online my particular suv (2019 Cadillac xt4 premium luxury) is known to have engine and other issues that don’t register codes and likely over 90% chance related to misdiagnosis or a band aid repair. *i have screenshots of dash, “my caddy”app alerts, etc*

Filed May 10, 2026 · Fuel system · OH

there is a recall on the 2021 cadillac xt4, fuel pump control module, N252516900, but my vin is not included. My vehicle seems to be having the same issue. The dealer has been unable to diagnose as it has been happening very sporadic and I don't drive often. Issue first occurred, vehicle would not start in June 2025, clicking noise, happened few times in December and now seems to occur more frequent. car will initially start but will stall and fail to start. vehicle usually starts and engine light stays on, but then engine light will go off within hours. Dealer indicated no error codes were stored. had onstar run a diagnostic today when I had issues and identified a fuel management system issue. In researching I located the recall notice and ran my vin.

Filed Nov 25, 2025 · Engine, Fuel system · 56,400 miles · CA

The contact owns a 2020 Cadillac XT4. The contact stated that upon starting the vehicle, the check engine warning light illuminated. The vehicle was taken to Auto Zone, where it was diagnosed and determined that the EVAP pump (Evaporative Emissions System) was leaking. The vehicle was not taken to the dealer or to an independent mechanic. The vehicle was not repaired. Additionally, the contact noticed that the fuel mileage of the vehicle was fluctuating. The contact stated that the vehicle made an abnormal sputtering sound and delayed starting while pressing the Push to Start button. The vehicle was not diagnosed or repaired. The manufacturer was made aware of the failure and referred the contact to the federal safety agency Hotline for assistance. The failure mileage was 56,400.

Filed Sep 22, 2025 · Brakes · 280 miles · FL

The contact owns a 2025 Cadillac XT4. The contact stated that while driving at various speeds, the brake pedal was depressed to the floorboard, with the check engine and an unknown brake warning light illuminated. Due to the failure, the contact had the vehicle towed to a dealer, and the vehicle was diagnosed with a defective brake module. The vehicle was repaired under warranty. The contact stated that a week after the vehicle was repaired, the four tires seized while in reverse(R). The contact was able to drive the vehicle to the dealer, and the vehicle was serviced for a defective backup sensor. The contact stated that while driving at 20 MPH, the brake pedal depressed to the floorboard with the same warning lights illuminated. The contact continuously pumped the brake pedal to stop the vehicle and drove into an open parking lot. The contact was able to slow down enough to come to a complete stop and coasted into a parking lot. Due to the failure, the vehicle was towed back to the dealer where the vehicle was diagnosed with a defective brake module. The manufacturer was notified of the failure and the contact was informed that the part for the repair was on back order. The vehicle was not repaired and remained with the dealer. The failure mileage was approximately 280.

Filed Jun 9, 2025 · Brakes, Engine · PA

While driving on the highway, my vehicle suddenly engaged the brakes without any obstacle ahead, creating a dangerous and frightening situation. Immediately after this incident, the Check Engine and Transmission System warnings also appeared. This vehicle is still new, and it is completely unacceptable to experience failures in major systems like AEB, engine, and transmission. I have since learned about TSB #24-NA-053, which describes false AEB activations in XT4 models. My concern is that my vehicle may be affected. This car was purchased without notification of this issue from the dealership regarding the xt4 and obviously it was also not resolved upon my purchase of the car. My report from on star is below: From: OnStar Notifications [XXX] > Date: [XXX] EDT To: [XXX] Subject: Vehicle Diagnostics: These are the results from your recent On-Demand Diagnostic for your 2024 Cadillac XT4 OnStar(R) Dear [XXX] , Here are the results of your recent On-Demand Diagnostic request on your 2024 Cadillac XT4. ModuleDiagnostic CodeDiagnostic InformationRecommended Action ECM - Engine SystemP0700Transmission Control Module Requested Malfunction Indicator Lamp Illumination. The DTC is an informational DTC. The DTC indicates an emission related DTC set in the Transmission Control Module.Service within 7 days SDM - Airbag SystemNoneNo Error Code FoundNone VIU - OnStar SystemNoneNo Error Code FoundNone TCM - Transmission SystemU0447Vehicle network communication code. The network provides a communications link between systems inside the vehicle and when the network is disrupted a code can be set. If vehicle functionality is impacted please seek service soon.Service within 7 days BOI - Bulb Outage IndicatorsNoneNo Error Code FoundNone ABS - Braking and Stability SystemNoneNo E INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed May 3, 2025 · Acceleration, Engine · PA

While driving the vehicle on 01 May 2025, the car rapidly decelerated from over 60MPH to under 30 MPH in an instant. The car would not go over 30MPH. The power steering was off, the safety restraint was off, service transmission warning was on, engine light was on,low fuel indicator was on (I had over a half tank of gas), and service stabilitrak was on. The car had to be towed to the dealership. This is the second time this has occurred within the last 45 days. I just purchased the car in the middle of March. This is extremely unsafe as if I was on a highway I would be injured, someone else would be injured or death. I filed a complaint on 20 March 2025 (Complaint No: 11649676).

Filed Mar 27, 2025 · Transmission · MD

I was in slow traffic and my check engine light came on then the parking brake engaged. My car stopped and I could not disengage the parking brake so the car could shift gears. I turned my car off for several minutes. When I turned the car back on, the check engine light and parking brake turned off and I was able to shift gears again.

Filed Mar 21, 2025 · Acceleration, Electrical · PA

While driving the car rapidly decelerated along with loss to steering control.The engine essentially shutdown and would not accelerate past 30 MPH with full force. Oil temperature was 280/300 and rising. Warnings came on the car stating service all wheel drive system,service safety restraint as airbags will not deploy, service transmission, service power steering along with the check engine light.I could not maneuver the car nor was the car drivable.Car was towed as it could not be driven.Car put myself and others at extreme risk.If I was on a highway myself or others would have been killed.Car was bought on [XXX].Incident occurred on [XXX]. Car was towed to Bergeys Cadillac Dealership in Plymouth Meeting PA and dealership proceeded to say nothing is wrong with the car.There is a class action suit against this exact issue with the same car and engine and dealership failed to acknowledge the issue and failed to let me return the car.Dealership has continued to say nothing is wrong with the vehicle. This is an extreme known safety hazard and GM/Cadillac needs to be accountable as people will die. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Dec 7, 2024 · Acceleration, Driver assistance · WA

I have a 2020 cadillac xt4. When I first purchased the car in 2021, it already needed a new battery. Since owning the vehicle, I've had to change the battery two times already with 3 years. When I go to start the car (push start) sometimes the car wouldn't turn over or turn on and my dash board would illuminate stating service stabilitrak. Sometimes it would take like 5-8 tries before the car turned on. When it did turn on, my check engine light came on, I couldn't accelerate beyond 43 miles, my braking system was not working and a lot of features on my car stopped working like the lane assistant didn't work, and neither did my cruise control, or emergency braking. Took it to O'Reilly and bought a new battery. Once I installed the new battery, the check engine light disappeared and the car started driving fine again.

Filed Dec 2, 2024 · Fuel system · VA

Had a check engine light occur after a dealer warranty installed engine. The dtc code was "po496". This turned out to be a parge pump failure. Vehicle is 4 years and 9 months old, milage at 34285. Dealer saying that part is not covered any longer under warranties of any type. The repair cost me $671.89. This is an extremely early failure of an emmisions control component.