My radiator fans are not coming on unless I run the a/c or heater. Changed temp control sensor and the relay with the 5 prongs. Switched the other 2 relays and still nothing when a/c or heater isnt on. Both fuses are fine. Is there a switch in the line somewhere? Manual just says to have computer checked.

Most often caused by a bad fan relay. This is a complicated system. Read the post below and download the GM wiring diagrams. Then check the fuses and relays. All 3 relays must be in perfect working order for the system to work properly.
Car overheats Ricks Free Auto Repair Advice

had the same problem in 1994 grand am, done all that and wiring harnness never found it , put jumper wire to ingition switch turn the key on fan came on.. its not right but it fixed it for ten years. before doing this check for power to relay look at plugs to relay and prongs for fuses. Some ans are controled by ingition switch, remove key from ring while running lift key see if it comes on

If the vehicle is not overheating then do nothing. There is a chance that the system is controlled by the vehicle computer and the fans in some vehicles only come on when the engine is under load, like when it's actually moving. Maybe sitting stationary and not working the engine it is normal for the fans not to run.

It can be faulty fan relay.The relay is not turning the system off.Or its wire short issue.Even with ignition off ,the fan relay is getting power so its not letting the fan to turn off.Bypass the fan control relay and see if still the fan works with ignition off or not.

For more troubleshooting check the link below:------

Cooling Fan Stays ON with Ignition Off?

http://whatisbyme.blogspot.in/2012/07/cooling-fan-stays-on-with-ignition-off.html
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Cooling fan relays location ?

http://technoanswers.blogspot.in/2012/02/cooling-fan-relays-location-on-1998.html
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DIC says "COOLING FAN FAULT"?

http://schematicsdiagram.blogspot.com/2011/12/dic-says-cooling-fan-fault.html
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Heater fan and headlights will not turn off with ignition off?

http://technoanswers.blogspot.com/2012/01/heater-fan-and-headlights-will-not-turn.html

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Fuel pump relay and cooling fan relay troubleshooting ?

http://repairhelpcenter.blogspot.com/2011/10/fuel-pump-relay-and-cooling-fan-relay.html

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Where Is Radiator Fan relay and Fuse Located?

http://schematicsdiagram.blogspot.com/2011/12/where-is-radiator-fan-relay-and-fuse.html

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These will help.
Thanks.

Replace your temperature sensor. There is a sensor specifically for the cooling fans that triggers the relays, and tells the fans to turn on/off. The relays won't energize unless it gets a signal from that sensor.

If she paid someone to replace her radiator she should take it back. There are temperature relays around the fan I believe and the fans are not working. These are right in the area of the radiator. Someone must have disconnected the fan or the relays were failing before the radiator was working. Either way, the car is not cooling and she sought a solution to that problem. She was charged and the problem is worse. Go back to the radiator place.

there is another temp sender on block 2 wire sensor that controls fans

Have you tested the fan, use a set of clip leads and supply 12 volts of battery power to the fan to see if it runs, another test is to disconnect the engine coolant temp fan switch, this sends the system into default and the fan will run.

The water temp sensor is located near the thermostat housing. This sensor is what tells the ECM to turn the fan on/off. The water temp sending unit is located near the same area. You know you have the correct sensor is because the water temp sensor has a 2 prong plug. The water temp sending unit only has 1 prong.

The fan relay may be malfunctioning (the fan relay is what actually switches the fan on and off and gets its signal from the ECM, which in turn gets its signal from the temp sensor) testing/replacing the relay and temp sensor would be the best thing to start with,... unless you notice any additional (non factory) wire attached to the power wires to the fan.  Sometimes folks, in an attmpt to fix  an overheating or fan relay problem, attach a ignition switched positive lead from the fusebox or other switched source to the positive poer lead on the fan,.. making the fan run whenever the ignition is switched on.