98 honda civic engine overheats, cooling fan does not turn on

Under the hood of the engine, close to the battery, there is a black plastic box. This is the Fuse Relay and Control Unit Box location. Remove this Box cover. The top of this box shows which fuses or relays control the different electrical components within the engine. On the Drivers's Side of this box (right-side if you are leaning over the bumber and radiator, and facing the windshield) you will see a radiator fan relay. You can pull this and take it to your local Parts store and ask them to test it. If it tests bad, then buy another (likely $20+). Do NOT keep driving your car until you get your radiator fan fixed, <this image should help you> because over-heating the engine could ruin your engine ($$$$).

Check the fuse panel for the fuse controlling your cooling fan. There should be a fuse block diagram in your Owner's Manual, and maybe one on the door panel to the fuse block assembly. If you have more than one fan, there may be more than one fuse.