Do you mean there's no "Air" blowing at all when you turn the heater on, or is it blowing air but not getting hot?
If no air at all, begin by checking the fuses. If fuses are good, then the blower or the wiring/connectors are bad. You'd need to remove the HVAC unit to get at this part. And it is very involved.
If you are getting air, but it isn't hot, then you're blend door inside the HVAC unit is faulty, or you have a blockage in the heater core or cooling system that stopping hot coolant from circulating properly. You'd still need to remove the HVAC unit.
If you want specific instructions for removing the unit, let me know and I'll send them to you.
Friday, November 19th, 2010 AT 3:41 PM