I recently had this problem with my '94 sedan. I changed all the bulbs as you did and the problem still remained. Long story short... I had a bad wire near the trunk lid hinge. I spliced it and the problem was fixed. Perhaps you have a short where your wiring enters the rear gate of your wagon. Wiggle the wires while someone is watching that obstinate dash light to see if it blinks at all... if it does, you found your problem! Hope this helps! :-)