The AC control on the console sometimes fails and causes problems. If the fan speed switch is turned all the way to the left, anti clockwise, the AC does not switch on so I guess if this control has failed then the AC and the engine fan could possibly not work. There is a thread on how to make the contacts on this module connect properly. It is a lot of work but might be worth it.
Does the fan work on a hot engine? Maybe I missed the answer to that question as it is an obvious one for someone to ask.