Cartrack unit doesn't respond

A Cartrack consultant phoned my wife to say to her that the car track unit in her car doesn't work anymore so Cartrack must come and replace it with a new one and she have to pay R870.00. I phoned Cartrack on the 17/04/2015 at 10:53am. I spoke to a gentleman, do not know what is his name and told him the story. I gave the username to him and he reported to me that the unit lasted send a signal the 24/05/2014. In the contract there stands, new equipment 1 year warranty. The unit was installed on the 27/08/2013. So that unit stop responding three (3) month's before the 1 year warranty expired. How can they expected us to pay for a new unit but is was faulty before the warranty expired. They just want to replace not even come and have a look to see that maybe the wires are lose. I want answers on the unit that stopped responding and want someone to come and check wires before they just want to replace. Please attend to my matter asap.