I appreciate the help regarding the Dodge ?2002? radiator fan relay switch, but I can?t find a replace part anywhere on the web. What I see is a replacement ?relay radiator fan? and nothing about a switch. I?ll definitely check for the relay switch, but I find it odd that I can?t find a separate replacement switch. Should I call NAPA?

it's not easy but it can be done, need a relay with harness and some wire. you must tap into the fan wire(positeve 12v) and run it to the switch side of the relay tap power(12v) constant to the relay and also a switch(12v) source and a ground ok it sounds hard but hre's a diagram
good luck

low charge pressure of 134A Coolant will not let the fan or compressor clutch engage.

I would check the fuses first then the fan relay , if you find two identical relays you just have to swap them to determine if there any good , if the fan starts working then get a new relay, if the fan still won't work then replace the fan thermo switch (usually located in the bottom part of the radiator facing the engine) if the fan still wont work then replace it. The best way to test the whole system out is to start the car and turn on the air conditioner (and blower fan) this should turn on both your fans, if the fans dont come on , check the fuses,relay and then fan motor then thermoswitch

The fan relay for the radiator electric fan is in the grille area, see enclosed picture. Thanks, don't forget to post a great comment about me!

RADIATOR FAN RELAY
The radiator fan relay is located below the left front headlamp module Radiator Fan Relay The headlamp module must be removed to access the relay.

REMOVAL
Open hood, disconnect and isolate the battery negative cable.
Remove the left side headlamp bulb from the headlamp housing.
Remove the left headlamp module.
Remove the cover over the relay.
Disconnect the relay connector Radiator Fan Relay
Carefully drill out the two retaining rivets.
Remove relay from vehicle.

you have an open or shorted condition detected in the low speed radiator fan relay control circuit. hope this will help!!!!

The relay is located down at the left lower corner of the radiator support. Little flat box, like a box of matches. common to be bad.

Either radiator fan switch or AC system fan activate relay. Check fan switch or look for AC fan motor fuse. Wiring diagram would help.

Don't rush to replace the fan itself until you have tested it. Check the fan relay and relay fuse inside the vehicle. Hopefully it will be just a failed relay and replacement ($12 at dealer) or/and an inexpensive 10amp or 30amp fuse. There can be multiple issues causing this code.

In my case, the fan relay failed (burnt). 2000 Dodge Durango. The PCM was also damaged and requires replacement, awaiting delivery. A remanufactured PCM can be purchased online for substantial less than at the dealer. We tested the fan by supplying power directly to the fan and it runs fine. We had to remove a cover (easy to remove) under the vehicle near the fan to gain access to the connector Use a fused link for testitng to prevent damage during the test. Using a multimeter, I found power 12.5volts from the 30amp fuse circuit which supplies the power for the fan, 12.5 volts from the PCM circuit with the key on, but only 5.16volts from the 10amp fuse circuit with the key on. A continuity test showed the 10amp fuse inside the fuse box inside the vehicle was good. The 30amp fuse in the power distribution box was good when tested for continuity. Checked resistance on all curcuits and they were well within limits. I also checked the wiring to the fan for continuity and resistance. After my tests were completed, a Dodge technican concluded the PCM is bad and is not grounding the circuit as it should. If you want to troubleshoot this yourself, see if your local library has access to ALLDATA which will have diagnostic information and the diagrams of the circuit involved. A Haynes manual for the vehicle, I purchased one at Autozone, can be helpful also.

It would appear that the relay is located on the cross rail that runs across the front of the vehicle (in front of the radiator). I found out that it is riveted in place by a single rivet, so in order to replace mine, I will have to remove the rivet and use a self-tapping screw to secure a new one.
The fan relay is located in the fuse panel located under the hood beside the battery. It will be marked under the lid. Make sure you check the maxi fuse for the fan also.