99 civic ex cooling fan issue
 

fellow Honda lovers need your help here!
my wife's civic cooling fan will not come on on its own but when i jump the fan switch it does, let me give ya a detail breakdown and maybe you guys/gals can see something i am not seeing. mind you i have alil mech skills so i am not a total nube at this,but maybe you guys can help me.
i have changed:
thermostat x2/fan switch/fan relay/changed the water pump because i just did the timing belt, flushed and drained the radiator and all is good on that end. so here is what i have done trouble shooting wise. i made up a plug to attached to the fan temp switch so i can see if its closing or not using a multi-meter.
i ran the car for 20min to make sure i had gotten all air out of system with radiator cap off, coolant bubbled a couple of times when the thermostat opened & coolant boiled over once or twice. fan temp switch closed while i had multi-meter on it so i know that worked. i jumped the fan switch with paperclip & fan came on but once i reattach the fan switch plug back to the sensor the fan doesn't want to come on. i allowed the car to run for 20 plus minutes and no fan. Temp on gauge stays at "normal op" never gets above that at least while its idling. why isn't the fan coming on? what am i missing here? please help so i can put the wife's nerves at ease. thanks

cooling fan
 

did you ever solve this problem because my 96 civic is behaving the same way. new thermostat/new ect sensor/new sensor on the head but fan will only turn on when shorted. what to check next?

Did you check the radiator fan relay?

switch relays but no fan. removed the thermostat and cooling fan worked when water temp was right.