Instrument panel not working on a 1991 ls400

What make , model an year vehicle ? If a GM vehicle 2003 to 2006 stepper motors in the instrument cluster are bad .
How to repair GM Instrument Cluster Speedometer Gauge Stepper

Check fuse for gauges. If ok, try banging on top of dash above instrument panel to see if they begin to work again. If they do, possible loose connection or defective cluster

Usually when these Gauges go out it is because of a faulty BCM( Body Control Module) The BCM controls all dash instruments . If it is the BCM you will have to get a dealership to flash the new one. Before doing that though check all fuses under hood and inside. It should say gauges or BCM

It's more likely a fuse is blown, the tail lights are on the same fuse as the dash illumination, check the tail lights if they are not working replace the fuse marked 'tail' in the fuse panel on the inside at the left side of the dash under the cover. At the same time check the 'gauge' fuse', there is a fuse location diagram on the cover.

It is the plug in harness just behind the instrument panel! I had the same problem! Try this for quit fix. Hit both sides of the dash on both sides of the steering wheel. (causes harness to make connections) try a couple of times. Long term fix remove dash clean and slightly bend prongs on wiring harness.

Check wire harness that goes to the trunk lid , it's attached to the left hinge . If it has broken and shorted wire , it may make your custer to go craizy.

Take out the instrument cluster, there is a plug in the middle of the cluster in the back. Several phillips screws hold the circuit board to the cluster. If you look real close there will be cracked solder joints where these pins are soldered to the board. resolder any pins that are suspect. you may have to get a good magnifying glass and good light to see it.

you will have to replace the complete speed/tack
asy. they are know for going out. very common.try internet for good deals on reman units.

What is the light on my lexus ls400 that looks some what like a dome what does it mean