'85 dash instrument cluster question

[netnarc2]

I've removed the dashboard instrument cluster and have it on the work bench. I'm replacing the light bulbs. I have the screws removed from the first circuit board but the ground harness which connects the first circuit board to the second board is tough to unplug. It's the cream colored piece of plastic that has all of the ground "poles" running into it. Any suggestions on how to get this thing unplugged so that I can remove the first circuit board to get to the light bulb bases? It appears that the ground harness which is attached to the first cicuit board (hardwired - soldered) should just slide up and off with the circuit board that it's soldered to, however it dosen't seem to want to lift up and off. Thanks.

 

[larry bud]

I have an 86, but can't you get to the lights from the front of the panel? You shouldn't have had to remove the entire cluster to change a couple of light bulbs.

 

[netnarc2]

Thanks. I knew about the fact that you can open the little metal "port holes" to gain access to the light bulbs, but it didn't seem secure enough to pull the bulb out of the base and insert a glass bottom bulb into the slot in the old base. Since this is a project car, and I don't have to rely on it to be ready in the morning to go to work, I thought that I would go ahead and replace the bulbs from the back side, so that I could replace the bases with new bases and bulbs. I had the unit all apart, but I couldn't get that printed circuit board off of the unit, because the ground unit just wouldn't budge. I took it to the Corvette parts store, Coast Corvette, and Gene told me that you just have to work the thing back and forth until the ground unit loosens up and lets you slide the printed circuit board off. I took it home and messed with it until I finally said "screw it" and "I'm going to end up breaking this circuit board, then I'll be in a world of do-do". So I was able to lift the cicuit board up just enough to replace the burned out bulb with a new one and put the unit back together. I used curved needle nose plyers to insert the bulb and base into the hole and turn and lock it. It was the only one I could access this way. Put it all back together and put the car back together and the new bulb works. Of course, it's brighter than the old bulbs, but at least I can see my temperature reading clearly. I watch the temperature gauge the most. I ordered a set of bulbs from the Corvette parts store, so that when I find out what the "magic" is to remove the printed circuit board ground unit, I'll tear it all apart and do it again. By the time I get done with this I'll be an expert. While I had it apart, I did some "repairs" on some of the broken dashboard parts that are usually hidden from sight. I think the WWF wrestled in this car.

 

[geekinavette]

Gene is correct, you just have to work it back-and-forth carefully. Try to apply the pressure as close to that board-to-board connector as you can so as not to flex the PC board. It'll make some unnerving "squeaking" type noises as it breaks loose, so don't freak when you hear that, it just means the connections are breaking loose. BTW...that's not just a ground connector, it carries various signals as well.

Bill

 

[netnarc2]

Bill, I got too nervous worrying about breaking the PCB and gave up and put it back together. I'll try again some day.

 

[wescarver]

Speedometer numbers fading away

My speedometer numbers are fading away from left to right. The center and right clusters are still very clear and readable. Is this similar to your problem and fixable by pulling the cluster?

 

[muskiemike]

I have an 84', with 30K miles on it.

Assuming the cluster on my 84 is the same as the 85, I was able to remove the circuit board and replace the original haligon lamps that apparently get way too hot and burn up the PCB, I replaced them with special Stanely non haligun bulbs and they are nice and bright, and apparently will last much longer.

 

[muskiemike]

I have an 84', with 30K miles on it.

Assuming the cluster on my 84 is the same as the 85, I was able to remove the circuit board and replace the original haligon lamps that apparently get way too hot and burn up the PCB, I replaced them with special Stanely non haligun bulbs and they are nice and bright, and apparently will last much longer.

Use the Stanley 7073 (3.5 CW)– replacement bulbs for the 1989 Xenon Bulbs The original 882’s have 3.8 CW - but are very, very hot

 

[mdsbch]

I just replaced all of my bulbs in the digital dash a couple of weeks ago on my 85 coupe. Here is a link that explains how to remove the cluster take it apart change bulbs and make repairs. I replaced all my 882 bulbs with 168's (they are twice as bright as the 194's that are recomended).

Home page link for repairs - http://www.batee.com/corvette/index.shtml

Link directly to the digital dash repair - http://www.batee.com/corvette/dcrg/repair.htm

Hope this helps.

Mike