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Help Troubleshooting Cooling Fans

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I have googled til my eyes bled. Hard to find some clear answers and I was hoping someone can help.


I have a 2011 2.5i and noticed that the rad fans were not coming on. I connected to an app to monitor and noticed that the coolant temp kept climbing when at idle (stuck in traffic jams).


When I was at home I popped the hood and let the car idle. Temps hit over 200 and the fans were not coming on.


There are 3 relays; main fan2 (light grey), main fan (blue) and sub fan (blue). The two blue relays are the same.


I cannot locate the fuses for the fans. The underhood diagram does not say and a few are marked as SBF and a number. All fuses over 20A do not look blown.


I tested the sub fan (guessing it is the one on the passenger side) by quickly applying 12v...it spun


I pulled at the relays and any fuse over 20A and put them back in (in case bad connection). I did not see any corrosion.


Fans are still not running.


I turned on the AC and the main fan (driving side one) came on and cooled the temps. I think it is suppose to do this regardless of coolant temp.


I swapped the two blue relays (main fan and sub fan) and with the AC on the main fan comes on. So they might be fine


So I know the fans are working if they get voltage. I know the two blue relays are fine (assuming they turn on the fan when the AC is on).


I could not test the main fan2 relay (grey).


SO I am puzzled.


One troubleshooting step suggested the engine coolant temperature sensor but it did not say where it was located or how to test it.



Where are the fuses for the fans located?

Where is the temperature sensor located?


thanks for the help. I am scratching my head

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The car temps are normal when cruising. It is only when isling (ex. stuck in stop and go traffic) when they start to climb. I tested it when I got home and let the car idle while I monitored the temps. The temps hit 203 without the fans coming on. I turned on teh AC and the main fan runs and brings the coolant temps down to 190-196 (normal).


Since the ODB2 reader is getting temps from the sensor I ruled out the sensor as a problem.


I found the fuses and they are fine. I need reading glasses...lol


The DRL relay is the same as the Main Fan2 relay (grey) so I swapped them. The DRLs are still working. So that relay is not the problem.


Down to the two blue relays possibly being the problem. If that is not the trouble then maybe somewhere in the wiring?


Anyone run into similar situations?

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Check the last pages here and see if theres a link to the service manual.


305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.


Engine Build - Click Here

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As an update I was able to get the sub fan to run. It was possibly not connected properly.


Check the manual for fan operation. The fans first go to low speed at 212F then shortly afterwards they go to high speed until 204F then shut off. Not quite what the table shows but I heard there may be more than one table out there for the same model.


So I have at least fans running.



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