auxillary fan on sub radiator

[urvandub]

the nissan urvan has a sub radiator and an auxillary fan bolted to it. my question is, when does it really start to run? my temperature reaches the second marker on the gauge, sometimes i would hear the subtle hum of the fan on que and the temperature would go back down to the first marker, to cool the temperature enough as if it was morning, even on a heavy traffic. but sometimes the temperature would stay on the second marker, and the fan won't run. is it time to pull out the thermo switch and replace it with a new one? or am i just to paranoid that my engine would overheat. when does the fan really start?. being a tinkerer, i am planning to hook the wiring to the auxillary fan on the aircon to make it go in sync, with of course a relay for safety. but, is it really necessary?

[v6dreamer]

The auxillary electric fan engage only when your engine need it to. Most car have 2 or 3 temp switches. ONE--tells the gauge in you car how hot it is. TWO--tells your fan to kick on at a predetermined temp. THREE-- tells your eng computer what the temp is.

So as long as your temp is normal, dont worry too much.

[s_quilicot]

how much and where to buy low tem thermo switch?

sa mga AC shops ba?

TIA