Google Nest thermostat E103 error: Problem with the Y1 wire

Google Nest thermostat 3rd generation. Air Conditioning unit: Goodman. The unit stopped running. The thermostat showed E103 error: Your thermostat cannot control this equipment properly without wiring changes. The issue was the definite purpose electrical contactor (General Electric CR453CB3HBAFG, Goodman part #B13603-21) 1 pole, 25 Amp, 24V Steps I took to fix the issue (this is not an advice; to reliably diagnose and repair your unit, contact a technician): 1. turned off the power for furnace 2. disconnected the power for the AC 3. gained access to the contactor 4. removed the 2 side wires 5. used a digital multimeter to test its electrical resistance (Ohms) between the 2 terminals. A functional 24V coil should read between 10 and 20 Ohms. If the multimeter reads close to 0 Ohms, the contactor is shorted 6. replaced the defective contactor with a new one 7. connected the power for the AC 8. tested 9. turned on the power for furnace