Deluxe instrument cluster to 9C1 cluster swap

[deesandvees]

Swapped out my deluxe instrument cluster for a 9C1 cluster and I'm getting some weird results.

1. No instrument cluster lights.
2. Turn signals work externally but the right signal makes the instrument cluster lights flash on and off in unison with signal as well as the brights indicator light.
3. Bright indicator light stays on regardless if brights are on or not.
4. Fuel guage does not work.

The 9C1 cluster plugged right in. Kind of a pain working with the speedo cable when reinstalling the cluster. I eliminated the speed sensor because I've eliminated the ECU so unfortunately no more cruise control (oh well I rarely would have used it anyway).

It's so nice to have that 120mph guage in front of me I just wish I could get it to work correctly.

[deesandvees]

Well folks it turns out all that's happening with my 9C1 instrument cluster is perfectly normal. You see, the stamped circuit for the deluxe instrument cluster and the 9C1 cluster are completely different. So my conclusion is you CAN'T directly swap out a deluxe instrument cluster for a 9C1 cluster. I'm guessing that the standard cluster can be directly swapped out for the 9C1 cluster so you guys with the standard cluster have got it easy. And for you standard cluster guys, there's no reason you shouldn't have a 9C1 cluster in your vehicle because it's really easy to find one and install it, and when you're mobbin in the triple digits and you get pulled over and the cop asks "do you know how fast you were going?" you can reply, "yes officer as a matter of fact thanks to my certified police speedometer I do know how fast I was going."

So my new idea is that I can get a standard cluster or 9C1 cluster harness from the junkyard and swap it out with the deluxe cluster harness in my '87 and then the 9C1 cluster will work and all will be well.

I considered altering the circuit board on my extra 9C1 cluster (I have two) but I don't think my brain operates on that level, of course I've got nothing to lose but an extra cluster. I got what I needed from it already (gear indicator spring and cable and cluster bezel).

Long live anything 9C1! Anybody that's swapped their standard cluster for the 9C1 speak up and reassure me that it's plug and play please.

[mike561]

I know this is kinda off subject but theres also aftermarket digital guages for box caprices, i looked at them and it seems like you'd have to be some electrical genious to get it to work 100% right though, i diddnt think it'd be worth all the money time and aggravation.

[deesandvees]

I'm not into the digital aftermarket stuff, but if the '90 Caprice had a digital dash you'd bet I'd have that in my '87 in a heartbeat. After a few epiphanies tonight I started comparing the schematics in my electrical service manual and some diagrams I drew up comparing the 9C1 cluster to the deluxe cluster. It looks like I might be able to switch around the almost 30 wires within the connector that feeds the cluster, I hope.

I'll post a "how to" when and if I do this right. I might just see if I can get the harness from a standard or 9C1 car a the junkyard, depending on how much is involved in getting it from the back of the fusebox and seperated from the other wires under the dash.

[deesandvees]

I finished the swap. I compared both schematics and drew out what the 9C1 cluster needed and rewired the instrument cluster connector to take care of it all. Weird that the only thing that doesn't work is the right turn signal indicator. Not sure why because it shares the same ground as the left turn signal and the power wire for it is one of the more obvious of the wires and it's connector location. Tested the bulb and it's good. I can hear the turn signal clicking and it works on the outside but no good on the cluster.