Came out to call for a blank thermostat. Customer stated that thermostat went blank and nothing was working, and only hears something in the closet that’s on. I checked system over and found the thermostat has gone blank due to the condensation pump not operating properly. Pump is on, but not pumping out the water. I tested the pump when I was out here a few weeks ago for the maintenance and it worked fine. Pump has failed and needs to be replaced. Customer approved pump replacement. I replaced the condensate pump, and cleared the tubing to make sure it wasn’t plugged. Wired in new pump to furnace controls and tested new pump with 4 liters of water. New pump is operating properly. I cycled AC on before I left to make sure system is cooling like it should. AC is now functioning properly and thermostat is working as well.