My engine fan turns on when I turn the ignition on but not the engine. Why does it do that?
I have a 1999 Toyota Corolla and when I turn the ignition switch on the motor fan turns on without the engine being on. The engine is cold and everything. I have researched and found out which relay switches are for each fan and replaced them, I have replaced the engine coolant sensor next to the thermostat, and I have replaced the computer. Granted all replacement parts were used. Relays were taken from a junk yard but had 6 total relays of the same numbers, and 2 sensors. I am playing off of the odds that there is no way that all relays and sensors are bad, and the computer I ordered was used as well. I do not believe its the computer but wanted to try. The car does not overheat or have any other malfunctions. My only concern is that the fan may eventually burn out from constantly running, and that its something that I want to know what is wrong with it. Do you have any idea what it could be?


