i have a 92 dual core radiator, i put it in my 89 civic. i dont think the fan is coming on, i used the main fan from the stock radiator, i use jumper wires to test the motor and it works. how can i check to see if the switch is bad or circuit or whatever. have a haynes manual and it says the thermal fan switch is on the radiator, and neithor the stock radiator or the new radiator have a switch on them. any help would be reatly appreciated.

 

well check this out man... your fan is powered by 2 wires... 1 runs to your ecu... and that is based of of your cars temp when it goes on. If you temp sensor isnt connected right i dont believe ur fan will work.... best thing to do is check all ur wiring and then if u cant get it to work wire it to a fuse that is on just when your car is on or buy a switch and wire it to that
if you dont understand this pm me and ill go over it with you in detail
At least you know the fan works
mike

 

yea i guess i will have to check all the wires, so there isnt a switch, just a temp guage, i mean i know thats working. i understand about the switch, and if i wasnt planning on selling the car thas what i would do. would it warm up ok if the fan was constantly running? o and thanx for all the help, you repied to another post and i notice that you are a very helpful member, just wanted to say thanx.

 

you can make a switch yourself if worst comes to worst. when your driving you dont need the fan, and when you are stuck in traffic you manually turn that bad larry on. my fan runs constantly, cause i like it that way

 

ya i wired my fan to be on all the time

 

89 civic fan switch is located in the rear of the motor.

Sometimes my former 89 hb has to idle for 30 mins before the fan kicks on. If the wires are backwards the fan will work just not correctly. It will take a way long time to kick on.

Pop your hood grab a beer and a chair (a radio helps) and sit and watch your fan and a wrist watch lol.

also on the 88-91 d15-d16 there are 3 sensors related to coolant.
Fan controll in the rear of the motor and 2 under the head. 1 for your teemp gauge (i believe that one is the single wire) and a 2 wire one that runs to the ecu. The one in the rear is just basially a thermo switch.