I am providing you with the wiring diagrams for the seat heater circuit, 2 of them, and the climate control circuit, 1 of them.
Inspect all grounds for tight, corrsosion free fir that has good contact with bare metal. Then inspect wiring for bare spots where insulation has come off. You may have to run the trouble codes to get a better idea. Any Advance Auto or Auto Zone will do this for free.
You may have a bad heating element, but I I understand you right the A/C cooling circuit cuts out too. Try to find common electrical components or wires in the wriing diagrams that are shared betrween systems and inspect those.
Images (Click to enlarge)
Friday, January 6th, 2012 AT 3:25 AM