Recently purchased a 86 240 sedan for my daughter. The Temperature gauge doesn't seem to work ever. At night when you turn the lights on the instrument cluster typically goes black. The overdrive indicator light is on when the overdrive isn't engaged and goes off when it is. The brightness control seems to be in reverse and actually affects the engine temp gauge. low bright = high engine temp, vice versa. At times the instrument cluster comes on dimly and everything seems as it should be but then it flashes and goes back to nothing. I don't have a clue where to start here, I pulled the dash apart yesterday, cleaned all the terminals and that didn't seem to make a difference. I would appreciate any help you can give me... thanks!