whaaaaaaaaaaa? no heater? what has the world come to!
you might be mistaken man,as per suzuki site,heater is available.
you havnt removed thermostat valve from the car,did you? cuz heater work from coolant flow of radiator,and if T-valve isnt there,your car might be running with temp needle right at C or little above occasionally.in that case,heater wont work,period!