You can start the engine without inserting the key.
CAUTION
To prevent damaging the smart key:
Panic button
Mechanical keyHyundai Tucson (LM) 2010-2015 Service Manual: Pressure Sensor Description and Operation
Description
The 4WD ECU makes a Motor Pump(Actuator) turn round for
generating an oil pressure. And then it presses a multiple disk clutch
and transfers the generated torque into rear wheels. Its torque value
varies according to a pressure status. ...
Hyundai Tucson (LM) 2010-2015 Service Manual: Troubleshooting
Failure Diagnosis
1.
In principle, ESC and TCS controls are prohibited in case of ABS failure.
2.
When ESC or TCS fails, only the failed system control is prohibited.
3.
However, when the solenoid valve relay should be turned off in case of ESC failure, refer to the ABS fail-safe.
4.
...