Heaters has sropped working?

Hi im totally new to this but after reading some of the faults im quite scared.
My Grand Scenic 1.9 DCi 06 has now got the heater problem that so many of you are complining about.
The fuse in glove box is ok and the heater on dash says on but heaters not blowing. (any ideas!!!)
Since i have owned the car i have had to put up with juddering when pulling away, Brakes making a noise when in reverse, 3 x check injection, 1 window regulater, 2 x steering ajdustment (main dealer recall)
Is this just my car thats playing up or are all scenics like this???
The repair costs are out of contol on this car and i can honestly say i will never buy from Renault again.