Basic Temperature Control Troubleshooting ?
 

Ok, I'm troubleshooting my lack of heat. The rear blower works but I'm not getting heat so the heat exhchanger temp sensor is the suspect. Bentley says to test it by checking the resistance at Harness connector "C" in the heater control module between the seats. However, where do I put the other lead, ground?

Most of the time what has happened is the cable end popped off the socket up at the controller between the seats. Pull the housing and inspect.

i'd crawl underneath first to see if your flapper boxes are opening.....

I'd just put the car away for the winter. Now if the AC wasn't working then I do something, because the only reason for me buying the PORSCHE was so that I could have an Air Condition sportcar in the summer. If i wanted to drive a HOT car I would drive one of my Lotus.

I agree with Kurt and Bell. It is most likely cable related and the flapper box isn't directing hot air into the cabin.

Found the problem. The servo linkage was disengaged. Once I reconnected that everything was toasty again. Thanks for all of the suggestions.