radiator fan not working

With the engine cold, unplug the coolant temperature sensor and start the engine. The check engine light will come on, ignore it. The radiator cooling fans should come on immediately at high speed. If they don't, you can replace all three fan relays in the underhood fuse box, they're cheap. The four pin ones are for each fan, low speed. The five pin one is for both fans, high speed. On a side note, if the engine is overheating it's most likely a blown head gasket. All Northstar engines blow head gaskets sooner or later. To confirm this have the coolant tested for exhaust gasses. If the test is positive, don't go any further with it. At this point it's not worth fixing. Jim

If the fan blades are plastic they can be razor sharp ! From spinning through road dirt