OE Tachs and Non-Tach Wiring

[nvrenuf]

I have a nice tach cluster I want to put into my 91 K5. I was thinking this would be mostly plug & play but after comparing the cluster to a '91 wiring diagram I'm not so sure. I guess being tbi/computer controlled really changed things. Anyone done this?


Also, my dash has been apart for a while and I can't tell which way is "up" on the cluster plug. The side of the plug is numbered, is #1 on top or bottom when installed?

 

[b454rat]

What year is the tach dash? If it's 78/79 and newer it will have the same wiring. Trace the circuits on both and see if they go to the same places. You might have to rewire some for the VSS on the speedo, but I don't think it's too hard to do. Also the plug goes in only one way.

 

[nvrenuf]

I don't know what year the cluster actually is, only that it's the newer style font. I'm not worried about the VSS as I intend to use the cable driven speedo.

I tried tracing the circuits and comparing it to the 91 diagram, it looks different but I swear it made me dizzy. Really the only thing I was tracing was the small gauges but they look different. I'll study it some more.

I thought the plug only went one way but I didn't notice a key so that confused me. I haven't actually tried to plug it up yet.

 

[b454rat]

If its the newer font, and going with cable speedo, it will/should be a plug and play.

 

[USSkoval]

I had thought that the pinouts were completely different on the '90-'91 clusters. Even if they are, you should be able to move the wires around to different spots in the connector.

 

[nvrenuf]

I had thought that the pinouts were completely different on the '90-'91 clusters. Even if they are, you should be able to move the wires around to different spots in the connector.

That's what I think I ran into but I was so dizzy and cross-eyed from switching between the circuit board and diagram I had to walk away. I was planning on needing to repin the gas gauge anyway but the others throw me a curve because I can't tell what each pole is and therefore where to move the pin to. I guess my biggest problem is that I don't have a diagram for the tach cluster.

I wish I could attach the 2 diagrams, it'd be so much easier to show than talk about.

 

[Metrodps]

Use a tester and connect one lead to the back where plug hooks up then use the other lead and check which gauge post it goes to. It is hard for me to type it. I looked at doing this with gauges in a idiot light set up and it is a PIA but can be done. I will be up for a little while if you want PM me and I will call you to try and explain.