electric fan not coming on?need help

This could take some serious checking. I have an 89, and had this. I believe the 91 is somewhat different.

In general, in these, the fan is controlled by the IRCM (integrated relay control module) or CCRM ( constant control relay module, I think). On my 89 LX it it a box under the dash to the left of the steering column that has 6 or 8 wires. A 91 or later may have the 10 wire CCRM that is mounted on the pass inner fender, under the hood. These turn the fan on based on both, or either, of the temp sensor and, or demand for AC. The EEC power relay is also operated from here on some. General function of both types is similar. Thank God, 5.0's don't have these...

The major issue is that, especially with the one mounted under the dash, battery power is sent to the module, and the fan is powered thru a relay that is on the circuit board in the module. So full power/amperage for the fan goes through the thing. The wire terminal connectors apparently get tired, the connection gets dirty, fails, overheat, and melt the plastic connector. Then you get no connection or such a poor one that the fan wont run, even when commanded on by the EEC and the IRCM.

If, with a demand for the fan, such as by the ac, you have power into the box, but none at the fan connector, this may be the issue.

Ford, and parts stores sell connector repair or pigtail kits to fix it. About $20. I melted the connector on two of them. The circuit board survived, but I also bought a new circuit board from Ford, $125. I replaced the fan motor just because. Then the new fan motor died. Instead of checking it out, I reinstalled the original fan motor and put a relay by the battery, operated by the former fan power wire, to run the fan. It has worked for almost 2 years, including 2 ac seasons...

At the time done it on the cheap on my 89 turbo.Done this on underdash type control.I ran a wire to solder joint of coil of relay. I think wire 1 and 8 spliced into will also work ran them to a external relay to the coil. I then cut wire 2 and 5 from relay put connections on them and plugged to normally open terminals on the relay. Board contols function as before. Amperage not on terminal strip. It has been like this about 8months works normal with temp sensor or AC . Remeber solder all joints.Hope this helps