Mystery Switch

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Elliot W

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CT
First Name
Elliot
Truck Year
1974
Truck Model
C10
Engine Size
5.3
I’m trying to figure out what this switch is in the truck. It’s got the wood paneling on it that seems to match the trim but not sure if these were aftermarket accessories in the 70s/80s.

The switch connects to light green and dark green wires on the steering column. From my research it looks like these could be for reverse lights which might make sense since the truck was a manual column shift but the PO switched it to a floor shift manual, but the lights don’t come on. All fuses look good. The wires go to the rear of the harness and then behind the fuse box. Any guesses would be appreciated.
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Doppleganger

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OH-MI: Just like it sounds
First Name
Chris
Truck Year
1985
Truck Model
K20
Engine Size
5.7
I would find that connector / wires on a schematic and see what those 2 connections do. Or, take a DVOM and check continuity between them and the fuse box - at least see what circuit the PO was accessing.
 

Elliot W

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1974
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C10
Engine Size
5.3
Thanks for the input guys! After a little testing today, I was able to determine it is the reverse light switch. There seems to be a bad ground somewhere as it will come on and go off with random combinations of lights to that corner.
 

dvdswan

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Port Orchard, WA
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Dave
Truck Year
1978
Truck Model
K10
Engine Size
350
You might look under the truck at the crossmember for the transmission. Due to age the clips that hold the wiring harness for the rear of the truck can easily be pinched by the crossmember being installed after do a clutch replacement. One of those been done that moments.
 

Elliot W

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Posts
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Location
CT
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Elliot
Truck Year
1974
Truck Model
C10
Engine Size
5.3
You might look under the truck at the crossmember for the transmission. Due to age the clips that hold the wiring harness for the rear of the truck can easily be pinched by the crossmember being installed after do a clutch replacement. One of those been done that moments.
Thanks Dave! Fortunately I've dodged pinching the rear harness after installing/removing/reinstalling the crossmember at least 5 times this year. I will say that my rear wire harness is looking tired though...the clips are definitely showing their age.

You live in Port Orchard? I lived there for 3 years...great spot. An hour to the city, mountains nearby, lots of waterways...I can't say enough about how much I liked it there. Sadly it looks like a few of my favorite places didn't make it (Slaughter County and Moon Dogs 2).
 

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