i'm starting a new thread ehre because I can no longer reply to the thread titled "1986 LED Instrument Cluster"
Here are step by step instructions for repairing the 2 most common causes of the instrument cluster failure:
1.Bulbs burned out---there is one piece of black plastic held in by 6 to 8 screws that you must remove before you can replace the bulbs. remove 4 screws right in front of the steering wheel, the other screws are on the side of the dash next to the doorjamb. Adjust your steering wheel to its lowest position. Once the screws are out you pull the plastic piece forward and work it out by bending the side part outward until you can tip the top of the piece forward. it shoudl then come out easily. the bulbs are located under the silver tabs on the front of the display. you can pry them out with a small screwdriver, then replace the bulbs with a pair of needle-nose pliers and a gentle touch.
- Short between circuitboards. For this you have to remove the entire instrument cluster unit. there are for hex bolts holding the cluster in. once these are removed, you can work the cluster out a bit until you see the connections on the right side. Use your needlenose pliers to remove the safety tabs and then the top connector. Then you can twist the top of the cluster towards you and wourk it out far enough to remove the lower, smaller connector. now twist the top of the cluster towards you and remove the unit. place the unit on a flat surface face down. remove the metal backing by loosening the hex screws. now you see two circuit boards, one on top of another. remove the hex screws holding the top circuit board in place. At the top right of the top circuit board you see a white plastic piece. look between the circuit boards under that piece, you can see there are metal pins connecting the two boards. both outer pins are ground. carefully remove the top circuitboard by working the pins out of the white connector. now you can use fine sandpaper to clean the pins on the lower board and some kind of small awl or screwdriver to clean the white connectors on the upper board. now reassemble the board and cluster unit, plug the cluster back in to the wiring harnesses and you shoudl see your cluster light up!