Radiator/Cooling Fan Not Turning On| P0480

[ruehiatus]

Hi everyone I've got an 18' Mk7 that's having some overheating issues.

Mod List(Pretty much stock):
Symposer delete
Muffler + Resonator Delete
Cobb AP dizzy stage 1 flash tune.




So this all started a few days back, I was overheating as it starts to get to the worst part of summer. (I live in Las Vegas so 100+ degree days are the norm.)
It looked like I was just out of coolant, so I topped it off and bled the system using the bleeder valve on the radiator.

Thats when I noticed if the car is not moving there is no AC/car overheats
initially, I thought I was having this issue because there was air trapped in the cooling system that needed to be bled out but I think that's fine. I've checked all the cooling fan relays and fuses.
I think somehow either my cooling fan blew or my coolant temp sensor is bad and not telling the fan to turn on at the correct time.


Guess my questions are: How can I narrow this down P0480 code to the fan assembly or my coolant temp sensor? Why would my fan stop working after topping off my coolant?

I'm new to working on cars any direction would help I've already used the search bar and did my research I wanna attempt to fix this myself before handing it off to someone else...

 

[slopoke]

Does the fan turn on when A/C is selected on? If it doesn't, I'd provide 12vdc directly to the fan to see if it operates. I'd also burp all of the hoses by removing the coolant cap and squeezing each hose to force any air bubbles out. If that does not help, I'd change the coolant temp sensor, I don't know how much it costs, but it shouldn't be too expensive. I'd also check to see if there are any blown fuses and make sure any relays in the control system are functioning correctly. I don't have a service manual for the Fiesta anymore, so I'm just going by normal troubleshooting proceedures. Good luck.

 

[FiestaSTdude]

My car was randomly overheating sometimes when I was stopped with the ac on. Thanks to the advice of a mechanic friend, I checked the fan and sure enough, whenever the car was overheating, the fan wasn’t running. I replaced my fan and fan shroud assembly and the problem hasn’t come up again.
I would confirm that your fan is running, turning on ac should force it on.

 

[ruehiatus]

My car was randomly overheating sometimes when I was stopped with the ac on. Thanks to the advice of a mechanic friend, I checked the fan and sure enough, whenever the car was overheating, the fan wasn’t running. I replaced my fan and fan shroud assembly and the problem hasn’t come up again.
I would confirm that your fan is running, turning on ac should force it on.

OK the AC does not turn the fan on so Im gonna say its the fan assembly

Where did you get your replacement parts from, did you do that yourself? How much did that run you?
Also if I replace the fan who's to say it won't just go right back out again... I wonder what caused it...



Thanks for the insightful replies

 

[slopoke]

OK the AC does not turn the fan on so Im gonna say its the fan assembly

Where did you get your replacement parts from, did you do that yourself? How much did that run you?
Also if I replace the fan who's to say it won't just go right back out again... I wonder what caused it...



Thanks for the insightful replies

Before you go and change the fan, check to see if the fan connector is getting 12vdc first. The fan could be good, but the control circuit could have a problem, such as a blown fuse or bad relay.

 

[ruehiatus]

I tested the fuses/relays that should affect the fan.
I would love to do the 12vdc test but I dont really see any info on doing that & no access to a multimeter (used a fuse tester) currently but I will try

 

[FiestaSTdude]

OK the AC does not turn the fan on so Im gonna say its the fan assembly

Where did you get your replacement parts from, did you do that yourself? How much did that run you?
Also if I replace the fan who's to say it won't just go right back out again... I wonder what caused it...



Thanks for the insightful replies

https://www.rockauto.com/en/catalog...081,cooling+system,radiator+fan+assembly,2181
I got the motorcraft one because I like spending way too much money on my Fist and I’m guessing it’s the highest quality one based on price.

 

[Intuit]

https://www.fiestastforum.com/threads/radiator-fan-problems.30509/

 

[TyphoonFiST]

https://www.rockauto.com/en/catalog...081,cooling+system,radiator+fan+assembly,2181
I got the motorcraft one because I like spending way too much money on my Fist and I’m guessing it’s the highest quality one based on price.

Dont ding around ...just buy the fomoco unit* easy out ...easy in.