Haroon, ABS work great on tarmac situation where it can prevent skidding by not completely locking the wheels. This lock/open in split seconds help vehicle to brake fast in a straight line than skidding. In off-road your friend need to find a way to switch off traction completely that will switch off ABS and with sightliest touch of brake, vehicle will just dig in and stop. And also while traction control is off you can spin the wheels nicely in sand while attacking the dunes. In many off-road rides these days there is a switch for on/off for traction control having icon of TC in a gear wheel. Read the manual and I am sure you will find it there, as after all its Jeep that is meant for off-roading and not only city cruise.