The temp has to go pretty high until the fans ficks in, it is somewhere about 3/4 on the temp gauge so it's certainly possible that your engine wasn't warm enough. I thought I had the same problem but today driving in the city I could see that they kicked in because the gauge went slowly up to 3/4, then slowly moved back to about 1/2 when the fans were active. I would have wanted to stop and visualy verify that they were operating but it was in middle of traffic and family in the car, but there is no other explanation. I.e. they worked as they should.
If the reading of your temperature gauge is correct that means that the sensor is working. The fans are controled by two signals from the PCM via three relays. You've verified that the fans are working and the relays are new so they should be working. I did like this when I tested the circuits from the relays to the fans:
I.e. carefully remove the cover of the relay and manually press the control arm. It has to be done very carefully to not break the cover and also be very carefull when removing them again to put the cover back as it's easy to break them.
I would suggest the following steps to verify that the fans and the signal that controls them are working:
* Use a ODB-II adapter to verify the actual temperature reading. As Lesterl and procaddytech the fans aren't activated until about 230 degrees Farenheight. Most likely the "problem" is that you don't reach sufficient temperature. If you A/C is working then turn it on as that will activate the fans earlier. I use a bluetooth ODB-II adapter so that I can connect it to my Android phone.
* Measure the signal on the PCM. I never got this far but I believe the control signals are open collector, they are definitly pull down at least (i.e. when they are active they pull the signal to the ground to make a circuit and activate the relay). If the circuit is working then you would be able to measure 12V on these outputs, if it is broken you should have some other voltage (should be 0 but can be some other voltage due to leak currents). The colors of the wires are dark green for the low fan speed control and dark blue for the high speed control. If dk green is low then fans are at half speed, if both are low then the fans are at full speed.