To cancel cruise control, do one of the following

o Press the brake pedal.
o Press the clutch pedal with a manual transaxle.
o Shift into N (Neutral) with an automatic transaxle.
o Press the CANCEL switch located on the steering wheel.
o Decrease the vehicle speed lower than the memory speed by 9 mph (15 km/h).
o Decrease the vehicle speed to less than approximately 25 mph (40 km/h).
Each of these actions will cancel cruise control operation (the SET indicator light in the instrument cluster will go off), but it will not turn the system off. If you wish to resume cruise control operation, push the RES/+ switch located on your steering wheel. You will return to your previously preset speed.
See also:
2012 Hyundai Elantra Review By Anthony Crawford
I’ve just driven a 42km loop in the base model Elantra Active with a
six-speed manual shifter and I can tell you unequivocally that the all-new
Elantra is a huge step up from the previous model.
...
To resume cruising speed at more than approximately 25 mph (40 km/h)
If any method other than the CRUISE ONOFF switch was used to cancel cruising
speed and the system is still activated, the most recent set speed will automatically
resume when the RES/+ switch is ...
40 MPG POWERTRAIN
Under the hood, the Hyundai Elantra is powered by an all-new 1.8-liter Nu
four-cylinder engine with 148 horsepower and 131 lb-ft of torque (145 horsepower
and 130 lb-ft of torque for Elantra PZEV) ...


