Question about free wire of glow plug system 6.2l Diesel

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German_fall_guy

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Location
Germany
First Name
Steffen
Truck Year
1984
Truck Model
K20
Engine Size
6.2 Diesel
My truck arrived yesterday and a got some questions about the truck. It is a 1984 K20 with 6.2l diesel engine.

in the first picture is a wire that comes out the glow plug wire loom on the driver side but all glow plugs are connected an no glow plug is missing a wire with connector also the coolant water sensor on the right side of the engine is no wire missing also. The color of the wire is green.

the secound picture shows glow plug controller switch but the middle bolt don’t have a wire. Is it correct? It looks like a bypass. It is a california truck but we have cold days right here. It the bypass good?!

So any help is welcome. Thx

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Blue Ox

Turning Diesel Fuel Into Fun
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I believe the extra wire is for the indicator light on the instrument panel.

They changed the whole relay and controller system in '85 so yours may be different than mine, but that's how mine is set up.

That solenoid does look like it's bypassed, which is not good. The glowplugs will not survive being on all the time. You're going to have to trace things and see what's up.
 
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German_fall_guy

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Engine Size
6.2 Diesel
where is the connector located for the indicator light on cluster
 

Blue Ox

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I'll have to look at mine tomorrow. My recollection is that the glow plugs/water in fuel lights have a separate harness that has it's own hole and grommet to pass through the firewall.
 

Blue Ox

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I tried to trace it, but it all kind of disappears into the main harness. My best guess is it's a three wire harness that goes through the firewall just below the fuse block. If you have cruise control it's right next to that one.
 

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