General LSX Automobile Discussion - Cooling Fan Always On - Any Suggestions

Over the last couple days both cooling fans come on as soon as car starts. They don't run with engine off and I checked relays - appear to be functioning OK. This is a cold start after sitting overnight. (99 Z28 - all stock)

After looking at wiring diagrams and some searching, I came to the conclusion it is either a bad ground or PCM is turning them on.

I started car and disconnected the A/C pressure switch. When I plugged it back in fans stopped. My guess is a bad A/C pressure switch but I'm looking for any other ideas before dropping $50 on a pressure switch that I won't be able to take back.

thoughts??

how about your coolant temp sensor? is it reading correctly on the dash? how about when you unplug that, see what the fans do.

how about your coolant temp sensor? is it reading correctly on the dash? how about when you unplug that, see what the fans do.

The guage reads same as always - cold when starting in morning, warm up and sits just under mid point when driving. If fans start tomorrow AM I'll pull this and see if anything different happens.