Honda Repair: cooling fans, coolant temperature switch, turning the key

Question
why when i star my civic 1991 the cooling fans star both of them  even just turning the key to star the car the fans will star

Answer
There is no common reason for why they might be staying on.  I have seen people wire them up directly to run all the time to compensate for an overheating problem.  You may also have a bad coolant temperature switch or a bad relay or even a bad PCM/ECM (computer).  There is no direct or easy answer for that one.