2004 ram 2500 5.9 diesel. Have a code p0483. the cooling fan will not come on. Even with the AC on. Looking for the problem . the question I have is will this condition affect the performance of the truck. It has no power at low speed but as long as you don't ask for much you would not notice. Problem started when the water pump failed and it overheated. Had a high temp code but have since cleared it. don't know if the fan problem is and outgrowth of the water pump ( it failed and water and anti-freeze went everywhere. any comment will be appreciated.