From no aircon gas to wiring being eaten by RATS!!

My husband bought a new IX35 Special addition about 3 months ago. Last week he switched on the aircon and realised it is not working. Phoned Hyundai and was informed to take the car to the nearest branch. Took it to Menlyn, Pta. Theytook out the pollen filters as it was dirty. Test the aircon - still not working. Phone Hyundai again. \Take your car to Silverlakes branch"where the car was bought. They told us the aircon gas is finished and must be replaced @ R800. My husband explained that its not acceptable as this car is about 3 months old and the aircon was never used as it was winter"