I'm going to nitpick the hell out of this. I've also got a damn cel for vss and o2 sensor heater on, but the o2 sensor heater is disabled and the vss is fine. It only comes on after like 20 minutes of driving.
I assume VSS is vehicle speed sensor? Maybe it's interpreting that your sitting idling at a low speed and kicking the fans on to get air moving. Why is the O2 sensor heater disabled -- doesn't that, well, help it work properly?