Chrysler Repair: 2001 t & c van 3.8 engine: no fan action, coolant temp, radiator fan

Question
The coolant fan will not come on. I have replaced the radiator fan module.  It still gives the code P1491 which is what it was doing to begin with. It has current going into the module the big red wire and the ground wire is grounded the two small wires I don't know where they go maybe the wiring harness some where. Can You Help?

Answer
Hi Doug,
The black/dark green wire at the relay pin 3 should be grounded at all times, the ground point being near the left headlamp assembly. The dark blue/violet wire on pin 4 is attached to the actuation coil of the relay and it comes from pin 1 of the green/blue plug on the back side of the intergrated power module that is under the hood, and that wire is internally connect to pin 18 of the natural/red plug nearby. The wire at that pin is colored brown/violet and goes to pin 73 of the engine computer which is what is responsible for energizing the relay by applying 12V to the wire and thus closing the points on the relay. So you may want to verify a connection between pin 73 and the pin 4 at the relay and also verify that it isn't shorted to ground when both plugs are disconnected.
If that proves out, then I would question the coolant temp sensor on the engine near the thermostat housing. It has a dark blue/dark green wire that is connected to pin 21 of the engine computer and a tan/black wire that is attached to pin 40 of the computer. The sensor itself should read in the range of 7-14,000 ohms when cold and drop down to 700-1000 ohms at operating temperture of the engine. That should provoke the appearance of the 12v on pin 73.
Let me know how this works out for you.
Roland
PS Sorry for the delay, I just found your question in the 'pool'.