the cooling fan relay is good but fan still wont come on what would be causin it

It could possibly be the cooling fan switch sensor, cooling fan engine, open wires between the fan relay and fan, or failing engine coolant temperature sensor. You can test the cooling fan engine by applying direct voltage via the relay location using a jumper wire. Remove the relay and with a piece of jumper wire connect both + and - ; if the fan does not turn on when the jumper wire closes the circuit you possibly have a bad cooling fan engine or an open/short in the wiring.