2005 dodge ram 2500 hemi. No gauges,no noise from starter, no box gear selector. Replaced batt and clamps, fuse box. Jump starter and cranks great.

SOURCE: blower motor makes loud noise when on high

I have a 2004 dodge ram 1500 with the same problem, vibrating blow fan when on high, pulled the blower fan out and found a piece of the hinge from the recirculation door and felt the recirculation door sitting up on the vent of its hinge. Crappy engineering once again.

SOURCE: what does the code p0300 mean on a 04 dodge ram

http://www.obd-codes.com/p0300

SOURCE: 2006 Dodge Ram 2500 diesel truck----need inside fuse box diagram

If you are looking for the fuse box diagrams or any other diagrams for your Ram, check promanuals.net for a factory service manual for around 20 bucks or so. It's an invaluable tool for my Ram 2500.

SOURCE: how tro replace heater core in 2003 dodge Ram PU

dodge want $800 to$1000 for doing this and I can see why.You have to raise or remove the whole dash recover you a/c freon ,disconect your a/c lines and heater hoses remove your heater box and put on a work bench remove the top and remove heater core,now next the last one I did the new heater core will not fit you have to modify the box so your new heater core will fit,put it all back together and fill with coolant and charge a/c, man I got tirered just typing this much less doing it, I hope this helps

SOURCE: 2006 dodge ram 2500 a/c fuse rely

The AC relay is located in the under hood fuse box. The cover should have a legend for location. Its one of the bigger black ones. You can rotate it with the horn or ABS one to see if its the problem. You may have a small fuse also in that box for it. If this doesn't solve the problem then you either have a leak or a computer problem. What a shop will do is try with a bidirectional data scanner turn the AC on. If they can't get it to turn on with a scanner then you most likely have a failed PCM if they verified you do not have low pressure or a relay or wiring or switch issue.