The saga continues... Cluster feed fuse

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Dman1049

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Chased wiring, pulled entire wiring harness in search of shorts. Found none. The pink wire ends up giving my HEI distributer power. Pink wire also runs to the ignition switch. Cluster feed fuse blows as soon as gauge cluster is plugged in and turn of the key. Pink wire is for cluster feed and B/U Dir signal fuse. See pics below. Any other ideas before I replace all wiring in the truck?

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Ricko1966

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Take a blown fuse push it into socket with a 2 pieces of wire 1 on each end put a light bulb in the wires using a light bulb as the fuse. Now do what you do to make it blow a fuse. When the light lights that's when it would blow a fuse. Now start taking things out of the circuit 1 at a time until the light goes out. When the light goes out the short is gone. I would probably start just by wiggling the crap out of harnesses watching for the light to blink. I have 1 other method but try this first.
 

Dman1049

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Have now replaced ignition switch and the wiring that runs through the colum for turn signals and what not. Soon as gauge cluster gets plugged in and keys is turned on cluster feed fuse blows. If the gauge cluster is not plugged in the fuse doesn't blow. This is the second gauge cluster. Other one did the same thing.
 

Ricko1966

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If it doesn't short until you plug in the gauge cluster you need to look real hard and behind the gauge cluster it's shorted or something behind it is touching it. Something touching it is my guess.
 

Dman1049

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If it doesn't short until you plug in the gauge cluster you need to look real hard and behind the gauge cluster it's shorted or something behind it is touching it. Something touching it is my guess.
Had it laying face down on the colum so nothing was touching the back.
 

Ricko1966

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Did you transfer anything from 1cluster to the other?
 

Ricko1966

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What ever happened with your Holley?
 

Bextreme04

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Are the clusters for your correct year? They have some differences in power distribution that can cause this to happen when switching between clusters from different years. It sounds like you have a short to ground on the power feed in the cluster. I suggest getting the wiring schematics for your truck and then try to figure out what pins should be in which spot in the harness to match the cluster.
 

Dman1049

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The cluster that came with the truck which was original as far as i know... 77 model year. Cluster in it now is a 73 model with tac. Other cluster had a fuel gauge where the tac is. I verified pins and all are in the corect place.
 
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K5ride

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I'm not sure but the pins might be different for several years. I'm getting ready to do my complete cluster and when I go online and price the cluster backing plate, it appears there are wiring differences. LMC lists them as 73-75, 76-77, and 78-80. I know they will all "fit" but I "assumed" the differences was how the circuits were wired. Again, I'm not sure. I'm just geting started to search info and getting ready to make the plunge.
 

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