I did the Electric fan upgrade on my 03 Suburban 2500 with 6.0 using the factory harness from an '05 Tahoe/Yukon. The fans operate properly to control the coolant temps, it does not turn the fans on when the compressor kicks on. I have the settings at AC Recirc and Serial Cycling. I have changed it to AC Recirc/Serial, Fan #2/serial cycling, Fan #2/serial, and just about every combination and no change other than the AC won't work at all.

My only settings options are, Hardware and Disable conditions. The hardware is set to AC recirc and serial cycling. The disable settings are disable at 4,000 RPM and re-enable at 3500 rpm, Disable TPS at 100% and Re-enable TPS at 75%. I've not been able to find any other options like I've seen in older threads that control the fans at certain speeds etc. just the hardware and disable. It's the original 6106 PCM.