I have a similar problem. I took the control panel off last year and struggled after replacing it to (what seemed to be) route that mentioned wire correctly again. Now it seems the cable is too long as it must now be routed somewhere different and shorter. I can easily get cold air, though as the cable is too long, the arm under the dash that the wire connects to does not move completely to the hot position.
Anyone know any tips for routing the wire correctly or getting that metal clip on somewhere that keeps the wire in place? I would just shorten the cable but you'll be losing the ends that allow it to attach correctly.
If it worked before it must work now somehow!