Electrical Gremlin

BrianX128

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So on my 7.3 I did the manual glow plug mod a few years ago, really just needed new glow plugs but I left it because it was all wired nice in my dash. Recently sometimes I'll press the button and the wait to start indicator will come on from the relay, but I have a second led wired to the output side that is feeding the glow plugs and it won't do anything. If I crank the engine for a couple of seconds it will wiggle something and it works and the output side light comes on, I can stop cranking and glow for 5-7 and it's fine.

I know it's likely a loose wire, but if it's not and my relay just isn't "jumping" theres no sense replacing the controller, just the relay since I'm manual now right?
 

yARIC008

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Didn’t completely follow your write up... But if you’re using a manual button then the controller is doing nothing. You’re just controlling the relay.
 

BrianX128

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That was essentially what I was trying to verify anyways. Turns out my relay was cracked in half and super "crunchy". I ordered a new relay from napa that I found referenced here over the last few years as the motorcraft relay on amazon has awful reviews and doesn't appear to be motorcraft anymore. Hopefully this one isn't garbage.

These are also in the worst possible spot on the truck to work on, there's no comfy way to get that far into the engine bay and play with tiny little parts and wires, you need one hand to hold yourself up leaning in that far and doing the rest of this one handed is a great time.
 

chillman88

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These are also in the worst possible spot on the truck to work on, there's no comfy way to get that far into the engine bay and play with tiny little parts and wires, you need one hand to hold yourself up leaning in that far and doing the rest of this one handed is a great time.

Pretty sure the one on my dually is going bad and this is the exact reason I haven't replaced it yet. Not looking forward to it lol.
 

BrianX128

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I made all of the wires longer for the smaller lugs, the bigger ones you can remove pretty easy. If it ever goes bad again I can at least pull it to the side to mess with it.
 
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