Looking for gauge cluster tach wire on a 91

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Girthrockwel

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I’m installing a Holley terminator x max on a 91 Silverado with a 5.3 swap. I didn’t do the engine swap and the wiring is a bit of a mess. The terminator has a tach output wire that I can connect directly to the factory tach but I can’t for the life of me get my hands on tach wire. I can’t tell where it goes to follow it to a connector. I’ve sliced my hands to shreds digging around behind the dash trying to find this thing and I’m at my wits end. I don’t want to disassemble my dash any more than I have to because it’s falling apart. If you can show me a picture you’d make my Christmas fudge list! Thanks in advance for the help.
 

Frank Enstein

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I don't have the schematics (they are on here somewhere somebody will post) but the wire should be light grey or white and it would have been connected to the coil. The coil was used as a jumper to feed power through it to the module and the negative wire from the module jumped to the tach wire.
 

Girthrockwel

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I’ve got a schematic for all of the wiring. I just can’t physically tell where the wire goes. From the big bulkhead connector on the backside of the cluster it goes into a giant taped up harness that splits off merges in with other bundles behind the dash. I’m thinking maybe it goes through the firewall at the pass through in the driver’s side footwell but I’m not sure.
 

PlayingWithTBI

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AuroraGirl

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If you cant find the wire from the tach or dont want to use that, the Alternator if its a CS130(d) or an AD230 has an alternator pin that can be used.
 

Girthrockwel

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If you cant find the wire from the tach or dont want to use that, the Alternator if its a CS130(d) or an AD230 has an alternator pin that can be used.
I found it using the wiring manual. That thing is awesome. Now I’ve got to figure out why all of my gauge cluster lights went out. When I test for continuity between the panel light fuse and the row in the convenience center that’s supposed to supply power I get nothing. I do however get continuity from the power side of the panel fuse slot to ground. Guess some wires shorted out somewhere.
 
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