I have an early model 86 coupe with cast heads...so I suppose it's more like an 85. My cluster has given me problems ever since I purchased the car, but the dash lights worked when the cluster worked. I just purchased a cluster from a forum member that came off an 89. Everything works well except for the lights. No lights when the ignition is turned on, or car running or when the headlights are turned on. I was told by a few different people that they were all interchangable except for some different wording where the shift indicator arrow is. Hell, I was thrilled to death just to see how much gas I had! Light bulbs all checked out fine. Anyways, does anyone know of any differences other than what I have already noted that would cause this? I wanted an 89 cluster because of the lack of issues they seemed to have that year. Anyone??

 

I own a L86 Coupe myself, and I believe the 89's use a different(non halogen) bulb to light up the display, as opposed to the 882 halogen bulbs used in the 85 to 88 displays. Dont know if that could be an issue in your case? Cheers!

 

Yes, the 89's use a zenon bulb, but I believe the circuts are the same as far as functionality is concerned

 

In Gordon Killebrew's book on digi clusters he separates the '89 cluster from the '84-'88 units but I haven't studied the details enough to know if there are any details other than bulb differences.

I see differences between '86 and later models.

 

Well, I was really hoping that I wouldn't have to open the thing up...being that I just got it...but after further investigation, it's looking more and more like a ground issue inside the unit. I took my other one apart a while back to see if I could fix it, but there were more than ground issues with that one. If I remember correctly, the ground pin where the two boards come together, had apparently unsoldered itself from exessive heat from the weak ground. After the fix, the lights worked fine while it was working for about 15-30 seconds....I didnt know how to fix the power supply problem which caused intermitent lighting, scrambled displays, ect. But that's why I bought this one. I have discovered with this one that not only is the lighting not working, but when I use the turn signal, the one not being used comes on ever so dimly and flashes in unison with the one I am using; I turn my hazards on and the high beam indicator flashes while the turn signal indicators are very dimly lit and flash in unison at the same time. I turn the high beams on with the headlights, and the high beam indicator lights up as it should, but the turn signal indicators both come on lit very dimly again. All of this and ALL the gauges work great....I just need to have a flashlight to see it or in the daylight if I really get close.
I am still trying to find out if there are differences in the wires leading to the pin connectors....

 

ttt

 

Well, I took the thing apart and cleaned the contacts that join the two circut boards and then reassembled everything and now it works fine.

The differences that I saw just from looking at the boards were not all that different....a 4 prong connector for the odometer instead of the two prong, the power supply was integrated directly into the top circut board instead of ziptied to it, the bottom board looked the same as all other years. I should have snapped some photos while I had it apart....

 

The cruise control circuitry which is part of the dash cluster is unique on the 89 dash cluster.

It also used a different cruise control servo from the 84 and 85-88's.

Did you test your cruise control to see if it works with the 89 cluster?

http://www.zip-products.com/Zip/prod...A3FF53CFD7AA7E

 

Well, not yet....but I am trying to keep everything as stock as possible. Maybe the same fellow that sold me the cluster will sell me the servo to go with it since I don't think the servo will work with the autometer gauges he replaced the cluster with...we'll see......