Second gens the dimmer is on the turn signal stalk.I'm not sure about your year, but the 3rd gen cars have a dimmer dial, located on the left side of the dash, near the traction control button and mirror controls. I would see if you can find the dimmer in your car and adjust it.
Thanks for the info!The variable control for the instrument panel and dashboard control illumination is on the stalk, but the electronic controller is under the dash, and that's probably failed.
There's a number of threads about this. Do a search for "illumination control module". Here's one: http://www.subaruoutback.org/forums...onics/20827-02-instrument-cluster-dimmer.html It has a wiring diagram attached.