how to fix light display on radio & overhead
See other post.
I have experienced similar issues with our '99 Montana. Try pushing hard on the overhead information display. On ours, most of the time, the display comes back to life which tells me there is a grounding problem and/or connection problem with the display. Separate but possibly related is the ground connection for the radio which (now correct me if I'm wrong...anybody else reading this post) is linked to the antenna connector on the back of the radio. I took the center trim off and the 2 screws holding the radio on and by wiggling the antenna connection wire, the radio display went back to normal, rather than they hyroglyphics I was seeing before. Overhead display also seems to be behaving itself (for how).
Update: I took the overhead display apart and found the display crystal on the pcboard had bad solder joints. The way I found the culprit was, I took the bare pcboard, plugged it back in and started the van. With a plastic probe, I pressed certain components and found if I pressed gently on the silver display driver, the display came back on. With a bit of surface soldering, the problem was fixed. I will post a picture of which specific part was the culprit. Hopefully this will fix yours as well. As for the radio, definitely a grounding issue. Ours still scrambles once in a while
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