Take your foot off the pedal and press the -/SET button when you reach the desired speed.
The moment you release the -/SET button, the set speed is fixed, and cruise control begins. The CRUISE CONTROL indicator comes on.
During cruise control, Straight Driving Assist Function is activated. This control function is an EPS function and it helps reduce the steering effort to keep the steering angle on a straight road with cants.
To Adjust the Vehicle Speed
Each time you press the RES/+ or -/SET button, the vehicle speed is increased or decreased by about 1 mph (1.6 km/h).
If you keep the RES/+ or -/SET button pressed, the vehicle speed increases or decreases until you release it. This speed is then set.
Honda Civic Service Manual. Hood Opener Cable Removal and Installation
8121C1
1.
Vehicle Lift
1.
Raise the vehicle on a lift, and make sure it is securely
supported.
2.
Front Wheel
...