Radiator fan won't come on

[IICrazy]

I let the car warm up and the fan never comes on. The fan is fine, I hardwired it just to test it out. swapped the thermostat and temp sensor. The fuse is good as well.


this is a 2002 GT??? any ideas? The

 

[GT Tommy]

Cooling fan motor not coming on?

Here is the 2003 GT Mustang 4.6 fan circuit diagram. Notice there are two fuses in the circuit, the 50 amp and 30 amp. Make sure you remove each fuse and check with a tester. Visual inspections are not dependable. Also, clean out your fan motor wire connector terminals. Use an electrical spray cleaner with a small flat screw driver. Make sure the terminals on both sides of your wire connectors are clean. Then get some di-electrical grease and pack the terminals with it before you connect the wire connectors back together. This will revent water from corroding the connection. If this does not solve your problem, then you have to back tract to your relay. Good luck, Tommy.

 

[COramprat]

Check to make sure you have power at the harness. Once you start the car and let it warm up you should have voltage on the low side. Let the get to the high side of normal and probe the the black and red/orange wire to see if you have voltage on the low speed side. Then turn on the AC and probe the black and orange/light blue to check high speed voltage. If no voltage I'd look into the CCRM as the relays may have gone bad.

 

[IICrazy]

Check to make sure you have power at the harness. Once you start the car and let it warm up you should have voltage on the low side. Let the get to the high side of normal and probe the the black and red/orange wire to see if you have voltage on the low speed side. Then turn on the AC and probe the black and orange/light blue to check high speed voltage. If no voltage I'd look into the CCRM as the relays may have gone bad.

After digging in the wiring diagrams on the HAYNES manual found the CCRM was bad, the High speed fan relay is toast, off to NAPA tomorrow for a relay.

 

[COramprat]

Might be hard to find one locally. I had to order one since none of the parts stores have it. I have one that still works if you get in a bind. Let me know.