First of all, the cooling fan circuit for diagnosing an electrical fault can first be examined for blown fuses. If the engine is overheating and the fan will not activate, check out its fuses and wiring. The problem could also stem from the CHT sensor, fan control module, or PCM if there are no issues. Take it to a professional to have it diagnosed. Disconnect the battery pack, draw off the coolant, and jack up the car. Take out the radiator hose, splash shield, and air filter housing. In some cases there may be more steps depending on what kind of engine is in use. Remove the wire harness clips and take out the fan shroud assembly. Reinstall using reverse steps, then test for leaks and check that the fan works correctly.