Cooling fans

You must use a test light to check for power and ground. Here is a guide that will help you:

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Here is another guide which is for a blower motor but uses the same theory:

https://www.2carpros.com/articles/blower-motor-testing

Please let us know hat you find so it can help others.