Radiator fan is not coming on while stuck in traffic and car runs hot. I have replaced the radiator, water pump and thermastat, and still my car runs hot only while stuck in traffic, and I don't hear the fan kick on. However, when I turn the A/C on the fans come on. Where would a sensor be for the radiator so I can replace it?

SOURCE: Radiator fan runs when car is cold but not hot

Try running a scan.

There must be a sensor problem though.

SOURCE: Radiator fan is not kicking on when it should

First off, I would disconnect the power supply to the fan and let the engine heat up to operating temperature and use a simple volt meter (you can purchase one at walmart or any part store for $5-15) to see if any voltage is even getting to the fan, it is possible that the fan motor could have failed. Also, you can run a couple wires directly from the battery to the fan ( one for negative, one for positive) it shouldn't matter if you switch up which is which on the fan, as a DC motor will just spin in reverse if you swap the polarity. This will rule out the possibility of the fan.

SOURCE: Radiator Fan don't work

try a hot wire from the battery to a swich to the fan you turn it on and off cools engine

SOURCE: 1994 Mits 3000gt. The radiator fan will not come

there is a heat sencing unit on the fan or radiator which cuts in and out to let the engine maintain operating temperature. If this is faulty, the fan will never go on and the car will overheat.

If you can not find this switch let me know.

SOURCE: cooling fans won't turn on. I replaced temp

On the relay you should have 12 volts at 2 slots terminal 30 has power all the time terminal 86 has power when then computer tells the relay to turn on fan, for cooling or a/c, terminal 85 is ground(-) for the 86 terminal to energize the relay to send 12volt from terminal 30 thru relay and out terminal 87 going to fans, sounds to me like computer not getting the signal to relay, you did get for blow fuse? and does fans come on with a/c on?