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Navigation backlighting fail. I'm baffled.

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Old Feb 23, 2019 | 06:01 PM
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Default Navigation backlighting fail. I'm baffled.

Maybe Yamae or someone can figure out my problem. The nightmare started when my navigation screen started fading out to white. It was brief episodes as first, then became more and more regular. The touchscreen would still respond to touch; you could change the radio channels with the screen white. Anyway, I thought it might be the ribbon cable was dirty or something. I took apart the unit, but the ribbon cable looked fine. After re-install the same symptoms were present so I bought another navigation screen off Ebay. Very good price and clean. Only problem--lcd backlights were burned out. Since the bulbs on my unit were working, I figured I'd just swap faceplates and all would be done. After swapping faces, I installed the unit and turned the key. The screen defaulted to the climate screen but none of the buttons worked. Had the Ebay seller sold me a piece of junk? I put the faceplate the unit came with back on and plugged it into the dash. It worked. Huh? I checked the part numbers. Same part numbers. So now the plan changed. I'd put new bulbs into the Ebay unit and all would be great. Even though I've never soldered anything in my life and am an electronics illiterate, I thought I could handle the job of replacing the bulbs, no problem. Oops. Wrong again, Einstein.

After reading this thread https://www.clublexus.com/forums/ls-...backlight.html , I bought the bulbs mentioned in the thread, bought a soldering kit off Ebay, and set to work. Getting the tiny bulbs de-soldered was a real pain. After half melting the first plastic holder, I finally got it out and replaced the bulb, then soldered it back in. The other bulbs went a little smoother, but it was a tedious, time-consuming job. Then I put it all back together, put it in the car, and fired it up. The bulbs worked. Not much else did. All the buttons on the faceplate were unresponsive. The symptoms were almost identical to when I just swapped the face-plates on the units. I pulled the unit out and put my old one back in. Swapping my old one back in managed to burn out most of my lcd backlight bulbs. One still worked. Driving with the bulbs out irritated me. You can guess what I did next. Oh, yeah, I pulled it out and soldered in two new bulbs, even as the voice in my head, said, "Don't do it, idiot!" I put it back in, and the faceplate is unresponsive, just like the first time. And the second time. I thought maybe there was something wrong with these bulbs. I took out the two I soldered in, put it back in the car and fired it up. No difference. Then I took apart the Ebay unit again, did some ill-advised soldering on one of the bulbs that made that bulb useless, fiddled with the power cables and put it back together and put it in the car. I actually got some more activity from the lcds after doing this. Before, there were just dashes on the bottom of the lcds and some faint readout where the temperature usually is. "Outside temperature" was readily legible on the lcd now, as well as a some other markings, but it really wasn't coherent. So that's where I'm at with this thing. I get the feeling that it's something simple I'm missing. Before I give up and buy another unit, anyone have any advice? Besides let someone who knows what they're doing fix it?

Last edited by aptoslexus; Feb 23, 2019 at 06:06 PM.
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Old Feb 23, 2019 | 10:35 PM
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"faint readout where the temperature usually is. "Outside temperature" was readily legible on the lcd now" - this would be it. Is your screen still working though even the faceplate is out?
I tried doing in mine for just some fading button change now that thing is dead I guess. The cables are so fragile to play with in first place so I won't even bother opening one now.

I have one I bought from eBay as well but its going through the same one as you said but only when its cold outside in the mornings the screen will be white but responsive, I just need to touch in place to activate the controls -- guess work and once its warm the screen picks up color and back to normal. Let me know if you want that shipped.
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Old Feb 25, 2019 | 11:54 AM
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Update. I was about to throw in the towel on this project. I decided to solder in the bulbs I took out of my original navigation unit and put in back in the car. If I had the same result, I was going to buy another one. The damn thing worked. And I don't know why. My best guess is that I didn't seat the ribbon cables properly in all my failed attempts. I did notice when I took it apart again that one was slightly crooked, so I paid particular attention to getting the cables seated correctly. So now I'm exactly back where I started. A screen that whites out, but with working climate control and backlight bulbs, lol. That was a lot of work to get back to the starting line. I'll have to re-check the Ebay unit and see if that isn't the problem.
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Old Feb 27, 2019 | 04:53 PM
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2nd update. All done. I have the Ebay unit installed and everything works. The original and ongoing snafu was indeed the ribbon cables, which are very particular about how they are installed.
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