the flow control valve to the heater core is malfunctioning. it is not allowing hot water to the heater core. we have a no heat situation. every other function is normal. how do I GET TO and service that valve.
There may be a air blend door controlling the heated air from the heater core. I recommend you purchase a service manual for the vehicle if you are going to work on this yourself. The factory manuals are by far the best to get and the investment will truely pay for itself in little time. Just this repair alone would justify the cost I think.
I believe Cougar is right. It is far more likely to be a blend door (could be nothing more than a vacuum hose loose) than not getting hot water to the core. Most modern cars feed hot water all the time. They just block the air to it.