Week ago lightening struck close to house and three speed fan stayed on high. Usually keep it at low speed. Pull chain and fan stops, pull chain again and fan goes to high only. Changed out pull chain switch and first pull fan goes to fast, second pull of chain and it goes to low, then third pull shuts it off. Could this be the little black capacitor box inside and if so where could part be found? Thank you.

So it only went to high with the original pullchain, then you replaced the pullchain and now you get high and low?

It sounds like a capacitor issue, but if so, the problem should have remained the same even with a new pullchain. You can try a new capacitor, they are available from the manufacturer, lampdepot.com, ceilingfanparts.com, and some places that sell fans also sell them.

http://www.ceiling-fans-n-more.com/ceiling-fan-capacitors.php