If the light for the glowplugs doesn't come on, I would eyeball the glowplug relay.

Twice in the last 9 months my light did not want to come on, the first time (somewhat out of frustration ) I gave the relay box a little "love-tap"...this motivated it enought to get things glowing again.
I imagine my relay is getting a little old, but I'll wait till it gives up the ghost before I replace it.
Might be worth checking out in your case.

-Larry



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