UPDATE:

mechanic said glow plugs were not getting power so he replaced the glow plug relay and it gets a light and starts right up.

But, I drove it for a day and now I'm getting the no-GP light problem again.

It is as if something is destroying my relays. He tested the power at the altenator and said it looked good. I haven't even called him to speak with him about the light not coming on again; I may just take it to the dealership.

Any ideas on what could be killing GP relays?

Thanks,
Matt