In my 1990 honda accord ex only one of the 2 cooling fans runs any ideas why? Or how to fix it?

You might want to try checking with a testlight to see if the other fan iseven gtting power. One is for airconditona and the other is for your cooling system so turn on your air and see if they both come on check all your fuseses and both relays under the hood take the relay from the one that does work and put it in the one that doesn't work to see if it's a relay problem