Windows, AC, and info board not working. Jeep Grand Cherokee

czar99

All 3 went out at the same time. No windows will roll down from any door (Sunroof works). Mechanic says condenser is getting fire. The info center works but no info displays. It says miles to empty but does not display the milage. temp is listed as --. Interior lights do not turn on when you open the door. Headlights do not auto come on at night. Buttons on steering wheel do not work volume or channel change. Mechanic ordered a new window switch (180) from dealer. Did not work, sending it back. He is saying it is the ECM computer and he does not do that, dealer. Any thing else to try, can I change the ECM? I see them on Ebay for 150 and they program the ECM for me.