I noticed last winter that my truck would not start when the temp was below 50. If the truck was plugged in it had no prob. I replaced all the glow plugs and it turns out it was the glow plug relay that had crapped out. I went to start up the truck last week and it wouldnt start. This relay has been fried, bad. It pratically fell apart as I took it out. I just finished put another one in. I was wondering if anyone had any ideas what would cause this to fry. At $76.00 a pop this is getting expensive.
Travis

This may help... I remember reading a long while ago that if the timer did not drop out the glow plugs, so they were on all the time. Seems like that would be a condition that would burn up a relay or more.

How would I tell if the timer was on the all the time? Wouldnt this drain the battery? The Diesel tech at Ford the realy can draw nearly 80 amps.
Travis

It wouldn't drain the battery since the engine is running. When you shut down the engine, all the power is off too.

The relay starts out at nearly 200 amps and gradually tapers down to about 80 amps. It is on for about two minutes then shuts off, not on all the time. Don't know why they burn u but they are pretty common, done three on my truck so far.