Dodge Repair: electrical issue: relay burns out

Question
QUESTION: I have an 02 dodge 2500 with a 5.9 Cummins. I have low voltage and a bad relay. I replaced the relay and blew it out again. What would cause the relay to overload and burn out so quickly?

ANSWER: Hi Ben,
What relay is it, and what do you mean by low voltage (which circuit or do you mean the voltage on the entire wiring system is low)?  I would check the electrical circuit that the relay services as it is probably shorted to ground and is overdrawing the current carrying capacity of the relay's switch contacts and dragging down the voltage on the system before it blows. Is this a Ram model?
Roland

---------- FOLLOW-UP ----------

QUESTION: thank you for your prompt response Roland. I put a new motor in this truck. yes its a ram model. during the test drive. my volt meter is on 8. I realize the alternator wasn't charging the batteries.I took it and had it tested and it came back good. I check the wires coming off the alternator with an ohm meter. and they are good all the way to the relay. I check the relay with the own meter. It was no good. I bought another one. On the test drive. It popped again. It was warm to the touch. I'm confused as to what would cause this. Thank you for your help.

ANSWER: The question is what is the electrical circuit that is served by this relay? Is there a name near it in the box where it is located. Once you know that circuit, then we may be able to find out why the circuit is drawing too much current. I have an '04 manual which may apply to your '02 model. But I need to know where the relay is located/what circuit it is powering.
Roland

---------- FOLLOW-UP ----------

QUESTION: According yo the wiring diagram I googled. The relay is in the ASD position in the box.

Answer
Hi Ben,
The 5.9 is a diesel and there is no autoshutdown relay needed for a diesel engine. So I wonder if it has a different purpose than is shown in the drawing that you looked at. Why not go look in the box and see if there is not a diagram there that shows the purposed of the relays in your truck. As far as I know there is no relay associated with the alternator in the '04 diesel, and I doubt it is needed in the '02 either.
I will go to bed in 30 minutes, so if I don't get your follow-up tonight I will get back to you tomorrow morning, first thing.
Roland