More or less what Bogey said ;
I'd first thing get my test light and clip it to a fuel injector pipe for a good ground , test it then turn on the key an rapidly touch the test light's point to each glow plug in turn to see if they're getting current .
If so , you almost certainly have some bad glow plugs .
If no current to the glow plugs , slide the GP relay's cover off and use the test light on the big stip fuseible link , it is held in by two phipllips screws that occasionally somehow work loose and loose contact .
Or , this part gets corroded , again halting the flow of current .
Then move on to unplugging the wires for further testing .
-Nate
Sid wrote :
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> I tried to start my '85 TD yesterday. I saw the indicator on the dash did not light up, and it wouldn't start. Obviously, the glow plugs didn't heat up, either. Is there a relay that needs to be looked at, and where would it be? The voltage in the battery is OK so it is not the problem.
> Sid, near Niagara Falls.
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