Been looking at the factory manual and haven't found a test to show if the temp wheel is working correctly. The man. has a "box" to hook up for the various systems checks, but no common sense way to see if the temp wheel is the culprit. Most of the "tests" end with "replace PBCU with no way to whittle it down. My forays into vaccum pod replacement now has the air going to the right place when the correct PB is selected, but I have no temp regulation. All I get is max heat or no heat with no consistent PB selection to help narrow it down. I get no A/C compressor engagement at all, as well. I am going to check a few other things in the system, but what is the easiest way to check the Temp wheel? Is it in the man. and I just can't find it? Thanks Hot In DEN...... I might add that the blower works as well, auto and manual.