Mark Vansaw

I recently purchased my first Corvette, an 89. The middle box in my dash with the 4 boxes for volts, mileage, oil pressure and such has the backlight bulbs not working all the time. Sometimes they light up and sometimes they dont. I checked the fuse, and all is good.

Do I need to replace the 4 bulbs in back, or could it be a small short? Thank you for your help, Mark

ccmano

DRM500RUBYZR-1

Absolutely!
Marty

Mark Vansaw

Thank you

billschroeder5842

As you remove your cluster, double check the contacts as they may be dirty. Sometime inconsistent performance can be traced to dirty contacts, This is especially true if the system works perfect one moment and then the next.... nothing.

Mark Vansaw

Thank you for your response. I have had it for a month now, but prior 15 years was only driven 1000 miles. Could that be an issue of just sitting for so many years?

mhobtr

I would check for a loose ground connection.

Paul Workman

Mark, there is a common ground "etch" trace on the printed circuit board that loops to all the sockets for the back lighting bulbs that originates at a large multi-pin connector. I had the same symptoms at one time as well. The pins were "frosted" with oxidation.

By polishing up the pins (power AND ground etch too) with a wire brush and electrical contact cleaner, paying special attention to the ground connection for the lights, I followed up by applying a thin coating of dielectric grease to the connector pins and reassembled the cluster.

Problem solved; took maybe 3 hours start to finish.

Ya gotta remove the cluster anyway if you were to send it off to Batee, IF it is still necessary to fix something after first cleaning the connections. So, perhaps you should try to give it a shot yourself. It doesn't take much effort once the cluster is removed to try cleaning the connector first. (Besides, Batee can't address the female half of the connector anyway unless you fly one of their techs out to your location so Batee can clean it for you)

Edit: Attached is a view of the PC board. Once you remove the PC board, you can use a pencil eraser to clean up the bulb contacts, followed by a quick spray of electrical contact cleaner (to prevent further oxidation).

IMPORTANT! Do remove a battery cable BEFORE removing the cluster, and attempting to clean the connector attached to the dash!

Note: Ignore the wires soldered to the board in this photo. (The picture was part of another post related to calibrating the tach.)
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