Q: engine cooling fan keeps running after car is turn ed off. New fan installed. problem still happens. aslo coolant and temperatu

A fault with a fuse would more likely result in non operation rather than continuous operation. ECM’s rarely go bad, indeed of the ones "claimed" to be bad, that is of those sent in as warranty returns, based on surveys fully half of those "returns" are perfectly good on subsequent testing. You might have a stuck relay and there may be other devices or controls in the circuit that are malfunctioning. The temperature sensor should be double checked. All that has to be checked with a wiring diagram in hand to make sense of the diagnostic. Your best bet is to request an electrical component diagnostic - radiator cooling fan circuit and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.