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Discussion Starter #1
I have a 2011 fiesta SFE (usa) and as the title says the radiator fan will not come on.

I have determined that the fuse does work and is getting power, the relay does work and is getting power. However I do not detect any power going to the fan when the engine is at operating temperature. I have heard that if the AC is on the fan will come on as well, however this is not the case for me.

This is only a problem with city driving, and if sitting to long the temperature light will come on. Turing the car off and running the heater fixes this however summer is to hot to allow this for to long.

It is possible that the temperature sending unit (the proper name escapes me) could be bad but I have not been able to locate it on the car, and I can not find a shop manual for this car to help me locate it.

Thanks for any help.
 

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Hey Hound, welcome to the Faction. I am thinking normally there is 2 relays , one for low speed and one for high speed. How did you verify relay worked? The temp sending unit is what is giving the dash reading of the temp, so that shouldn't have anything to do with the fans.. Turn on the ignition switch, and using your wiring diagram, locate the wire for the ground side of the relay coil. When you ground this wire, you should hear the relay click and the fan(s) should come on. If it does, then you know the wiring up to, and including the relay, are good. Now we know the problem is between the CTS and the relay.

If the fan doesn't come on, we need to continue with the relay and it's wiring. There are two current feeds, one for the relay coil and the other for the cooling fan(s). Using your wiring diagram, locate these feed wires and probe them with a test light. With the ignition key on, there should be power at both wires. If you have power to one and not the other, you have an open in the wire from the fuse to the relay.

If the fan doesn't come on, we need to continue with the relay and it's wiring. There are two current feeds, one for the relay coil and the other for the cooling fan(s). Using your wiring diagram, locate these feed wires and probe them with a test light. With the ignition key on, there should be power at both wires. If you have power to one and not the other, you have an open in the wire from the fuse to the relay.


You can jump across the fan relay to confirm the relay's failure.

If the fan doesn't come on, we need to continue with the relay and it's wiring. There are two current feeds, one for the relay coil and the other for the cooling fan(s). Using your wiring diagram, locate these feed wires and probe them with a test light. With the ignition key on, there should be power at both wires. If you have power to one and not the other, you have an open in the wire from the fuse to the relay.


You can jump across the fan relay to confirm the relay's failure.

On systems that have computer control using a sensor signal, you can make a similar test of the relay current feed terminals with a test light and the ignition key on.

If the current feeds are good, ground the relay's switch terminal (the one with the wire that goes to the coolant switch). If there's a sensor and the switch terminal wire goes to the PCM, unplug the wire before grounding the terminal. The relay should click and operate the fans. If it doesn't, replace the relay.

You may have trouble doing this with relays that plug into an under hood relay "center." Unplug the relay; turn on the ignition and with your test light probe the two current feed terminals in the relay center. If they pass (turning on the test light), make up short jumper wires to connect to the unplugged relay and one long jumper (that you run to an electrical ground) for the switch terminal. If the relay still doesn't work (ignition on), replace the relay. If the relay does click, probe the output terminal to the fan motor with a grounded test light. If the light goes on, the problem is in the wiring from relay to fan motor.

In my Mach since I race I actually spiced into the hi speed fan wire at the PCM and grounded it to a switch so in between rounds with motor off I can run the fan.

Also,If you disconnect the coolant temperature sensor the cooling fan should turn on (I think, this is kinda old school), when you do this check to see if the relay operates and you get 12 volts coming out of the relay .

Also, have you checked for a main 40 amp fuse that is located near the battery in the small fuse box ? I am assuming when you say fuse good, you probably checked the one inside the car??

http://www.scribd.com/doc/59749364/Ford-Fiesta-Electric-Schematic
 

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Discussion Starter #3
I used a test light to check the relay and fuse in the fuse box in the engine compartment and see that they were getting and giving power and swapped around the fuses and relays to test them in other fields. The blower motor for the heater is a great one to check. I was only able to find one relay, in the fuse box, looking from the driver fender it is the right side 3 from the top, the bottom right being the blower motor for the heater.

I'll give all this a shot on Tuesday, my next day off.

Thanks
 

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Is there a fuse inside the car in that box?, that I am not sure of, usually anything with a fan with a car that new is a relay/fuse. Good luck and let us know what you find!!
 

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Discussion Starter #5
The Schematic you linked to, what year is that for? The fuse box it shows does not look like the one in my 2011.
 

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Best thing to do is pull the relay and jumper with a piece of wire to see if the fan runs. If not running then check fan connector to see if you have power to fan and ground to fan. If both power and ground check fine, then you probably have a dead fan.

That's the old school way, the new way might be that the fan is controlled by a pwm signal from the computer. In this case the relay would supply power, and the ground side would get a pulse width modulated connection to ground to control the fan speed.

And yes the fan should run if the AC is on.
 

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Hi, I just tried replacing my new radiator fan on my 2011 ford fiesta, I got the part from carparts.com, replaced the 40a fuse and the fan still doesn't turn on at all.
 
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