I'm still not able to resolve this problem. I have verified the wiring and I am able to energize the A/C compressor from the Base Module. I had access to another AC control box (N22) and replaced it. Same problem. I did try this:
I disconnected the wire going to the A/C compressor clutch and put an analog meter on the line going back to the Base Module - when the AC is on (automatic) the engine idle rpm rises slowly and the voltage rises at the same time. When the idle drops, the voltage drops. The idle increases then decreases at about a 2-3 second rate. When the AC is off, the engine idles normally and the voltage drops to zero. The voltage never gets near the required 11-14 volts which is probably why the code 16 is triggered.
The TD signal brought out to the 38 pin connector-pin 13 is >3VAC per the shop manual. I can't find the location of the transducer that produces this signal since my documentation has errors. I checked all the fuses and holders for opens and the common funky contacts. (At least the ones that show up on my questionable schematic)
Summary: New engine wiring harness about 2 years ago
No codes other than Base Module - Code 16 (clutch shorted)
No AC Control Module (N22) codes
New AC compressor/clutch
Still need more suggestions --- Thanks