2026 Cadillac CT4 Adaptive Cruise Control User Guide
As part of its Driver Assist Package, the 2026 Cadillac CT4 offers Adaptive Cruise Control to Premium Luxury (and higher) trim levels. When cruise control is activated, this feature automatically maintains a safe following distance, improving comfort and convenience when driving on highways.
Cadillac Adaptive Cruise Control (Advanced) Guide
If equipped, Adaptive Cruise Control (ACC) allows the cruise control set speed and following gap to be selected. Read this entire section before using this system. The following gap is the following time between your vehicle and a vehicle detected directly ahead in your path, moving in the same direction. If no vehicle is detected in your path, ACC works like regular cruise control. ACC uses camera and radar sensors. See Radio Frequency Statement.
If a vehicle is detected in your path, ACC can speed up the vehicle or apply limited, moderate braking to maintain the selected following gap. To disengage ACC, apply the brake. If the Traction Control System (TCS) or StabiliTrak/Electronic Stability Control (ESC) system activates while ACC is engaged, ACC may automatically disengage. See Traction Control/Electronic Stability Control. When road conditions allow ACC to be safely used, ACC can be turned back on. ACC will not engage if the TCS or StabiliTrak/ESC electronic stability control system is disabled.
ACC can reduce the need for you to frequently brake and accelerate, especially when used on expressways, freeways, and interstate highways. When used on other roads, you may need to take over the control of braking or acceleration more often.
Warning
ACC has limited braking ability and may not have time to slow the vehicle down enough to avoid a collision with another vehicle you are following. This can occur when vehicles suddenly slow or stop ahead, or enter your lane. Also see “Alerting the Driver” in this section. Complete attention is always required while driving and you should be ready to take action and apply the brakes. See Defensive Driving.
Warning
ACC will not detect or brake for children, pedestrians, animals, or other objects.
Do not use ACC when:
- On winding and hilly roads or when the sensors are blocked by snow, ice, or dirt. The system may not detect a vehicle ahead. Keep the entire front of the vehicle clean.
- Visibility is low, such as in fog, rain, or snow conditions. ACC performance is limited under these conditions.
- On slippery roads where fast changes in tire traction can cause excessive wheel slip.
- When towing a trailer.
RES+: Press briefly to resume the previous set speed or to increase vehicle speed if ACC is already engaged. To increase speed by 1 km/h (1 mph), press RES+ to the first detent. To increase speed to the next 5 km/h (5 mph) mark on the speedometer, press RES+ to the second detent.
SET–: Press briefly to set the speed and activate ACC or to decrease vehicle speed if ACC is already engaged. To decrease speed by 1 km/h (1 mph), press SET− to the first detent. To decrease speed to the next 5 km/h (5 mph) mark on the speedometer, press SET− to the second detent.
Press to disengage ACC without erasing the selected set speed.
Press to select a following gap time (or distance) setting for ACC of Far, Medium, or Near.
The speedometer reading can be displayed in either English or metric units. See Instrument Cluster (Uplevel) Instrument Cluster (Base Level). The increment value used depends on the units displayed.
Switching Between ACC and Regular Cruise Control
To switch between ACC and regular cruise control, press and hold
When ACC is engaged, a green
indicator will be lit on the instrument cluster. When the regular cruise control is engaged, a green When the vehicle is turned on, the cruise control mode will be set to the last mode used before the vehicle was turned off.
Switch from ACC to regular cruise control only when there are no vehicles ahead of your vehicle.
Warning
Always check the cruise control indicator on the instrument cluster to determine which mode cruise control is in before using the feature. If ACC is not active, the vehicle will not automatically brake for other vehicles, which could cause a crash if the brakes are not applied manually. You and others could be seriously injured or killed.
Setting Adaptive Cruise Control
If is on when not in use, SET-/RES+ could be pressed by mistake and activate ACC when not desired. Keep off when cruise is not being used.
Select the set speed desired for ACC. This is the vehicle speed when no vehicle is detected in its path.
While the vehicle is moving, ACC will not set at a speed below a minimum speed, although it can be resumed. If equipped with Super Cruise, this minimum speed is 5 km/h (3 mph), otherwise, it is 25 km/h (15 mph). The minimum allowable set speed is 25 km/h (15 mph).
To set ACC while moving:
- Press .
- Accelerate to the desired speed.
- Press and release SET−.
- Remove your foot from the accelerator.
After ACC is set, it may immediately apply the brakes if a vehicle ahead is detected closer than the selected following gap.
ACC can also be set while the vehicle is stopped if ACC is on and the brake pedal is applied. The ACC indicator displays on the instrument cluster and Head-Up Display (HUD), if equipped. When ACC is turned on, the indicator light displays white. When ACC is engaged, the indicator light turns green.
Be mindful of speed limits, surrounding traffic speeds, and weather conditions when selecting the set speed.
Resuming a Set Speed
If ACC is set at a desired speed and then the brakes are applied, ACC is disengaged without erasing the set speed from memory.
To begin using ACC again, press RES+ up briefly while moving more than 5 km/h (3 mph). The vehicle returns to the previous set speed.
If the vehicle is stopped with the brake pedal applied, press RES+ and release the brake pedal. ACC will hold the vehicle until RES+ or the accelerator pedal is pressed.
A green ACC indicator and the set speed display on the instrument cluster. The vehicle ahead indicator may be flashing if a vehicle ahead was present and moved. See “Approaching and Following a Vehicle” later in this section. Once ACC has resumed, if there is no vehicle ahead, if the vehicle ahead is beyond the selected following gap, or if the vehicle has exited a sharp curve, then the vehicle speed will increase to the set speed.
Increasing Speed While ACC Is at a Set Speed
If ACC is already activated, do one of the following:
- Use the accelerator to get to the higher speed. Press SET– . Release the control and the accelerator pedal. The vehicle will now cruise at the higher speed.
When the accelerator pedal is pressed, ACC will not brake because it is overridden. The ACC indicator light will turn blue on the instrument panel and the HUD, if equipped - Press and hold RES+ until the desired set speed is displayed, then release it.
- To increase speed in smaller increments, press RES+ to the first detent. For each press, the vehicle goes 1 km/h (1 mph) faster.
- To increase speed in larger increments, press RES+ to the second detent. For each press, the vehicle speed increases to the next 5 km/h (5 mph) mark on the speedometer.
The set speed can also be increased while the vehicle is stopped.
- If stopped with the brake applied, press RES+ until the desired set speed is displayed.
- If ACC is holding the vehicle at a stop and there is another vehicle directly ahead, pressing RES+ will increase the set speed.
- Pressing RES+ when there is no longer a vehicle ahead or the vehicle ahead is pulling away and the brake is not applied will cause the ACC to resume.
When it is determined there is no vehicle ahead or the vehicle ahead is beyond the selected following gap, then the vehicle speed will increase to the set speed.
The speedometer reading can be displayed in either English or metric units. See Instrument Cluster (Uplevel) Instrument Cluster (Base Level). The increment value used depends on the units displayed.
Reducing Speed While ACC Is at a Set Speed
If ACC is already activated, do one of the following:
- Use the brake to get to the desired lower speed. Release the brake and press SET−. The vehicle will now cruise at the lower speed.
- Press and hold SET− until the desired lower speed is displayed, then release it.
- To decrease speed in smaller increments, press SET− to the first detent. For each press, the vehicle goes about 1 km/h (1 mph) slower.
- To decrease speed in larger increments, press or hold SET− to the second detent. For each press, the vehicle speed decreases to the next 5 km/h (5 mph) mark on the speedometer.
The set speed can also be decreased while the vehicle is stopped. - To decrease speed while the vehicle is stopped, press SET− until the desired set speed is displayed.
Selecting the Follow Distance Gap
When a slower moving vehicle is detected ahead within the selected following gap, ACC will adjust the vehicle’s speed and attempt to maintain the follow distance gap selected.
Press on the steering wheel to adjust the following gap. Each press cycles the gap button through three settings: Far, Medium, or Near.
When pressed, the current gap setting displays briefly on the instrument cluster and the HUD (if equipped). Subsequent presses cycle the gap button through three settings: Far, Medium, or Near. The gap setting will be maintained until it is changed.
Since each gap setting corresponds to a following time (Far, Medium, or Near), the following distance will vary based on vehicle speed. The faster the vehicle speed, the further back your vehicle will follow a vehicle detected ahead. Consider traffic and weather conditions when selecting the following gap. The range of selectable gaps may not be appropriate for all drivers and driving conditions.Changing the gap setting automatically changes the alert timing sensitivity (Far, Medium, or Near) for the Forward Collision Alert (FCA) feature. See Forward Collision Alert (FCA) System.
Courtesy Gap (If Equipped with Super Cruise)
Press and Hold on the steering wheel when vehicle is moving to temporarily increase the gap with the vehicle ahead to allow for merging traffic.
Press and Hold
Press RES+ or the accelerator pedal to resume ACC. Following distance gap will return to the original selection after hold.
Alerting the Driver
If ACC is engaged, driver action may be required when ACC cannot apply sufficient braking because of approaching a vehicle too rapidly.
When this condition occurs, the collision alert symbol will flash on the windshield. Either eight beeps will sound from the front, or both sides of the Safety Alert Seat will pulse five times. To view available settings for this feature, touch the Settings icon on the infotainment home page. Select “Vehicle” to display the list of available options and select “Collision/Detection Systems.”
Approaching and Following a Vehicle
The vehicle ahead indicator is in the instrument cluster and HUD display, if equipped.
The vehicle ahead indicator only displays when a vehicle is detected in your vehicle’s path moving in the same direction.
If this symbol is not displaying, ACC will not respond to or brake to vehicles ahead.
ACC automatically slows the vehicle down and adjusts vehicle speed to follow a detected vehicle ahead at the selected follow gap. The vehicle speed increases or decreases to follow a detected vehicle in front of your vehicle when that vehicle is traveling slower than your vehicle set speed. It may apply limited braking, if necessary. When braking is active, the brake lights will come on. The automatic braking may feel or sound different than if the brakes were applied manually. This is normal.
Passing a Vehicle While Using ACC
If the set speed is high enough, and the left turn signal is used to pass a vehicle ahead in the selected following gap, ACC may assist by gradually accelerating the vehicle prior to the lane change.
Warning
When using ACC to pass a vehicle or perform a lane change, the following distance to the vehicle being passed may be reduced. ACC may not apply sufficient acceleration or braking when passing a vehicle or performing a lane change. Always be ready to manually accelerate or brake to complete the pass or lane change.
Stationary or Very Slow-Moving Objects
Warning
ACC may not detect and react to stopped or slow-moving vehicles ahead of you. For example, the system may not brake for a vehicle it has never detected moving. This can occur in stop-and-go traffic or when a vehicle suddenly appears due to a vehicle ahead changing lanes. Your vehicle may not stop and could cause a crash. Use caution when using ACC. Your complete attention is always required while driving and you should be ready to take action and apply the brakes.
Irregular Objects Affecting ACC
ACC may have difficulty detecting the following objects:
- Vehicles with cargo extending from the back end.
- Non-standard shaped vehicles, such as vehicle transport, vehicles with a side car fitted, or horse carriages.
- Objects that are close to the front of your vehicle.
ACC Automatically Disengages
ACC may automatically disengage and you will need to manually apply the brakes to slow the vehicle when:
- The sensors are blocked.
- The Traction Control System (TCS) or StabiliTrak/ESC system has activated or been disabled.
- There is a fault in the system.
- The radar falsely reports blockage when driving in a desert or remote area with no other vehicles or roadside objects.
- A DIC message may display to indicate that ACC is temporarily unavailable.
The ACC indicator light will turn white when ACC is no longer active.
In some cases, when ACC will not activate, regular Cruise Control may be used. See “Switching Between ACC and Regular Cruise Control” previously in this section. Always consider driving conditions before using either cruise control system.
Notification to Resume ACC
ACC will maintain a follow gap behind a detected vehicle and slow your vehicle to a stop behind that vehicle.
If the stopped vehicle ahead has driven away and ACC has not resumed, the vehicle ahead indicator will flash as a reminder to check traffic ahead before proceeding. In addition, the left and right sides of the Safety Alert Seat will pulse three times, or three beeps will sound. Touch the Settings icon on the infotainment home page. Select “Vehicle” to display the list of available options and select ”Alert Type” and “Adaptive Cruise Go Notifier” in “Collision/Detection Systems”.
If equipped with Driver Attention System (DAS) located on top of the steering column, when the vehicle ahead drives away, and DAS determines if the driver’s attention is on the road ahead, ACC resumes automatically. See “Attention to the Road” under Super Cruise. If necessary, press RES+ or the accelerator pedal to resume ACC. If stopped for more than two minutes or if the driver door is opened and the driver seat belt is unbuckled, the ACC automatically applies the Electric Parking Brake (EPB) to hold the vehicle. The EPB status light will turn on. See Electric Parking Brake. To release the EPB, press the accelerator pedal.
A DIC warning message may display indicating to shift to P (Park) before exiting the vehicle.
Warning
If ACC has stopped the vehicle, and if ACC is disengaged, turned off, or canceled, the vehicle will no longer be held at a stop. The vehicle can move. When ACC is holding the vehicle at a stop, always be prepared to manually apply the brakes. Leaving the vehicle without placing it in P (Park) can be dangerous. Do not leave the vehicle while it is being held at a stop by ACC. Always place the vehicle in P (Park) and turn off the ignition before leaving the vehicle.
ACC Override
If using the accelerator pedal while ACC is active, the ACC indicator turns blue on the instrument cluster and in the HUD (if equipped) to indicate that automatic braking will not occur. ACC will resume operation when the accelerator pedal is not being pressed.
Warning
The ACC will not automatically apply the brakes if your foot is resting on the accelerator pedal. You could crash into a vehicle ahead of you.
Curves in the Road
Warning
On curves, ACC may not detect a vehicle ahead in your lane. You could be startled if the vehicle accelerates up to the set speed, especially when following a vehicle exiting or entering exit ramps. You could lose control of the vehicle or crash. Do not use ACC while driving on an entrance or exit ramp. Always be ready to use the brakes if necessary.
Warning
On curves, ACC may respond to a vehicle in another lane, or may not have time to react to a vehicle in your lane. You could crash into a vehicle ahead of you, or lose control of your vehicle. Give extra attention in curves and be ready to use the brakes if necessary. Select an appropriate speed while driving in curves.
ACC may operate differently in a sharp curve. It may reduce the vehicle speed if the curve is too sharp.
If equipped, the curve speed control indicator light 
ACC automatically slows the vehicle down while navigating the curve and may increase speed out of the curve, but will not exceed the set speed.
When following a vehicle and entering a curve, ACC may not detect the vehicle ahead and accelerate to the set speed. When this happens, the vehicle ahead indicator will not appear.
ACC may detect a vehicle that is not in your lane and apply the brakes.ACC may occasionally provide an alert and/or braking that is considered unnecessary. It could respond to vehicles in different lanes, signs, guardrails, and other stationary objects when entering or exiting a curve. This is normal operation. The vehicle does not need service.
Other Vehicle Lane Changes
Objects Not Directly in Front of Your Vehicle
The detection of objects in front of the vehicle may not be possible if:
- The vehicle or object ahead is not within your lane.
- The vehicle ahead is shifted, not centered, or is shifted to one side of the lane.
Driving in Narrow Lanes
Vehicles in adjacent traffic lanes or roadside objects may be incorrectly detected when located along the roadway.
Do Not Use ACC on Hills and When Towing a Trailer
Do not use ACC when driving on steep hills or when towing a trailer. ACC will not detect a vehicle in the lane while driving on steep hills. If the brakes are applied, ACC disengages.
Disengaging ACC
There are three ways to disengage ACC:
- Step lightly on the brake pedal.
- Press .
- Press .
Erasing Speed Memory
The ACC set speed is erased from memory if is pressed or if the ignition is turned off.
Weather Conditions Affecting ACC
System operation may be limited under snow, heavy rain, or road spray conditions.
Accessory Installations and Vehicle Modifications
Do not install or place any object around the front camera windshield area that would obstruct the front camera view.
Do not install objects on top of the vehicle that overhang and obstruct the front camera, such as a canoe, kayak, or other items.
Do not modify the hood, headlights, or fog lights, as this may limit the camera’s ability to detect an object.
Cleaning the Sensing System
The camera sensor on the windshield behind the rearview mirror and the radar sensors on the front of the vehicle can become blocked by snow, ice, dirt, or mud. These areas need to be cleaned for ACC to operate properly.
If ACC will not operate, regular Cruise Control may be available. See “Switching Between ACC and Regular Cruise Control” previously in this section. Always consider driving conditions before using either cruise control system.
For cleaning instructions, see “Washing the Vehicle” under Exterior Care.
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