You didn't specify what Civic you had so I looked at a DX Coupe.
Based off what you said it is the washer level switch located on the bottom of the windshield reservoir.
You could try inspecting the connector to ensure it is connected and in good working order. If that is okay then I have attached how to check out the system.
To me, the directions say to remove the bumper. I would see if you can just remove the washer container. Then I would remove the switch and keep it plugged in. Turn the key on and move the switch up and down. Depending on how it is made as you move the float up and down it may turn the light off on the dash then you will know it is the switch.
My thought, replace the switch.
Washer Level Switch Test (Canada)
Remove the front bumper.
Disconnect the 2P connectors from the washer.
Check for continuity between the terminals in each float position according to the table.
Monday, May 10th, 2021 AT 11:54 AM