Yes, I know this problem has been ongoing for quite a while. Your question has actually "timed out" for ay least, the second time. If you need more time, you can request that the question be "reopened".
Just so you know, you can still return to this thread and ask any "follow-up" questions that you may have about this same issue AT NO EXTRA CHARGE - even if you have "Accepted" my answer and "Rated" the service I have provided for you.
Anyway, I "mis-spoke" when I mentioned the "hydraulic" system and the "control solenoid" for your fan clutch. After looking at the service information again, I found that your fan is not one of the fans that hydraulic pressure to turn it like some of the newer vehicles. It DOES use an electronically-controlled viscous clutch however, and the PRINCIPLE that I have been trying to get across to you remains the same.
YES, you MAY have a defective fan clutch assembly. However, I do not recommend going out and buying one simply based on the codes that you are getting. Diagnostic Test Codes (DTCs) NEVER tell you which parts to replace. They only tell the technician diagnosing the vehicle WHICH DIAGNOSTIC CHART to use to get the problem diagnosed correctly. Properly following the instructions in the diagnostic test charts is how you go about figuring out which part of the system or circuit is causing the problem, and therefore which parts, if any, need to be replaced. The problem we are talking about on your truck could turn out to be a simple wiring repair.
Please download the PDF file HERE
Please note that the file will be deleted from the file server in a few days due to copyright restrictions, so you might want to save a copy to your computer for future reference.
I included the diagnostic test charts for BOTH of the codes that you posted. However, you probably will not need both of them to get your truck fixed.
First, note in the first diagnostic chart (for P0480) that I "highlighted" the possible causes for that code. As you can see, the fan clutch it self is listed, but there are also a lot of other possibilities listed. Using this chart will help you to determine which of the possibilities is the actual problem.
The second chart (for P0483), if you read step 1, sends you right back to the chart for P0480. (I highlighted that for you as well). So, you will want to start with P0480 in your diagnosis. Chances are that if you fix the problem that is causing P0480, the other code will go away on its own.
Pretty much ALL of the diagnostics here can be done with a simple digital multimeter. No high-dollar scan tool needed, like in some diagnostic routines....
The part where is says to go to "Powertrain Verification Test - Ver-1" simply means to clear the fault codes and drive the vehicle to see if the code returns. I figured you should be able to handle that OK on your own, so I did not include those instructions in the file.
Please remember to take a moment to rate the service I have provided. That is the ONLY way I get any credit at all for the effort I have put into this. Please also remember that you can still come back to this thread and ask any follow-up questions if you need to, as long as they are directly related to the subject of this thread.
I hope this helps you to finally get this issue resolved.