DD16 2011 engine fan constant

AC pressure switch sometimes,or the hub itself.How many miles on it?If it's been on the engine a lot of years the hub might be done.Can you hear any air leaks around the hub?

 

If you know a mechanic with the engine diagnostic program they can look and see if anything is sending the signal to keep the fan on,AC or water temp sensor or something.

 

FWIW; Mechanic told me once a lack of freon could cause a fan on a DD15 to run all the time. GL.

 

Did you mean you put air to the fan clutch? If you did that with the engine running and the fan didn't stop then it is the hub.

The fan solenoid is a little thing on the firewall. They rarely go bad. See if the hot lead on the solenoid plug has power. It's ground switched so the hot lead should always be hot when the engine is running.

It can also be the AC pressure switch. You can just replace it to find out. I think they are about $45.

I had the same problem with an '09 DD15 and it turned out to be a short in the wiring harness. There was a big plug under the oil cooler module. That's where the short was and it was a real bug hunt finding it.

There is another thread on this topic.
13 Cascadia DD15 Fan stays on New clutch, solenoid & press switch