The low coolant light when you have proper amount of fuel gets triggered by a faulty coolant level sensor.
The sensor is located at the bottom of the coolant reservoir. Check to see if it is connected properly and does not have any corrosion on the connector.
The high pitch noise could be the water pump. You could have a broken impeller inside the water pump.
Remember to only work on the cooling system when the engine is cold.
Here are some helpful articles:
I have attached the replacement procedure.
Please let me know of any questions.
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Monday, August 9th, 2021 AT 8:23 PM