I installed a simple ceiling fan with lights. It was removed from my step-son's house. Only 3 wires to hook up. Black(neg), white(pos) and green(ground). There are 2 pull chains. After install, fan works but lights do not. Tried other bulbs. They all said lights were working before removal.

Almost all fans have either a connector block and a blue hot lead for the light or a blue through lead. You need a separate lead since not everyone uses a light kit. Remove the light kit, 3 small screws, and look for a connector block or a blue wire.

Your saying black is negative and white is positive which tells me your saying black is neutral (negative) and white is Hot (positive). The black wire should always be the hot connected to the hot lead and the white should always be connected th the neutral (white) wire in the junction box.