Q: Engine fan non-stop running until you turn the ignition key off

A P2184 code indicates temp sensor circuit low. That means the voltage that the ECU reads on the temp sensor is low. The ECU interprets this as a hot engine and turns on the fan. A short circuit in the harness to the sensor could also give this indication. If you continue to get this code, then the next step is a Pin-Test at the ECU Harness. If you are not still seeing the P2184, then another possibility is that the cooling fan relay is stuck. The relay is controlled by the ECU, but it is actually the part that switches the fan on and off. Testing procedures for either of these components go beyond the scope of this forum. By contacting YourMechanic, you could have a technician come to your home or office and perform the tests to determine what needs to be replaced.