my buddy has a 2003 ram 1500 with the 5.9l no hemi or anything he has a p1491 code i searched and everyone says to check the 39 fuse well his does not have a fues for the 39 fuse and it has a mechanical fan so does anyone know what it means when it has the old 5.9 engine in it and that code

 

Did you look in your fuses under the hood? It should be for your electric ac fan. Your right on the fuse #39 but its in the box under the hood.