98 Gs400 Blank Navigation Screen

[MayorofEastCtown]

Hi guys,

I'm new to this forum and new to Lexus ownership as well. I've had many corolla's over the years and decided it was time to finally step it up and get a big boy Toyota. A few months ago I bought an immaculate 98 GS400 for $3800 from a guy in Ohio and when I say immaculate it was this guys baby, he may have even birthed it himself. The car has been working flawless for me and I absolutely love it. The only problem I've had so far, and the car came like this, is that the head unit screen comes up blank. I found another thread on here with two lonely Lexus owners with the same problem, but it was only merely stated by them and they couldn't find any solutions http://us.lexusownersclub.com/forums/topic/41111-2000-gs400-navigation-screen-blank/ (that should be the link to it). With that long winded backstory out of the way, now to the problem, a lot of which I stated in that thread.

When I turn my car on the screen comes to life and says Lexus in big dramatic letters, but then after that all it shows is a solid color screen, either black or yellow depending on what button I press (menu, destination, audio, etc..). The strange thing is that the outside temp, climate control, and radio station on screen bubbles still pop up and are perfectly clear, so I believe the display isn't completely gone. I can also still use the touch screen capability to click on things and hear the little beep noise it makes, but sadly I then have no idea what I clicked on. I've taken out and reinstalled the entire head unit and I've also taken out and reinstalled the nav computer in the trunk, I even tried using the nav computer without the hard drive in it (hopefully that didn't mess anything up). But at the end of the day I'm still sitting here looking at a solid color screen. Any ideas guys?

And if I did anything wrong in this post I'm most sincerely sorry, and will repent to the Japanese car gods.

[13IS250C]

Sorry I can't answer your question Peter, but I do want to welcome you to the club! Please post a pic of your new baby when you get a chance.

BTW, I love your avatar!

[MayorofEastCtown]

Thank you for the welcome! I'll definitely post a full write up and photos of my baby into the mega thread of them.

I'm glad you like it! A few minutes in Microsoft paint can help express my true feeling more than words ever could.

[pj8708]

Hi Peter and again welcome. I appreciate your writing skills!

Of course the first thing one would check is power/ fuse. But since you've got at least a color on the screen and letters when you turn it on that would not be your problem. Have you checked or researched re-booting the software? I don't have any personal experience with this, but I have heard of others looking into it. Another item is the wiring in the trunk hinges. At the time of manufacturer a problem with some of the wires rubbing as it passed through the trunk hinge channels started showing up.

You might try doing a search here and see if there have been any post regarding the trunk hinge wiring.

I think other members will chime in here and have more helpful information

Paul

[MayorofEastCtown]

Paul,

Sorry it's taken me so long to reply, America's birthday was a long celebration. I thought it could be the fuses as well, so I replaced the two radio ones and the cigarette lighter one. The reason I changed the one for the cigarette lighter is because one day I was trying to jam my phone charger in it and the screen vaguely showed up. I don't know if that was a coincidence or not, because I completely took apart the radio bay looking for loose wires and couldn't find any.

I saw in another thread how to get to the "advanced settings" menu, but since I couldn't see anything that I was pushing it degraded quickly. I'll look for the actual re-booting thread though.

I'll look for the trunk hinge threads as well. Though when I pulled back the carpet in my trunk the wires ran on the bottom of the trunk and came through the back seats around the lower back area. So I'm not sure if it's the same harness?

Thank you for all the leads!

Peter

[1990LS400]

A common way to deal with a dead generation 1 Lexus navigation screen is to install an HVAC control from a non-nav car (check eBay) and an aftermarket radio and/or radio/nav. I doubt that your problem has anything to do with trunk hinges or fuses.

[MayorofEastCtown]

That was going to be my next step if I reach the end of my patience with solving this. The previous owner actually gave me one when I bought the car. I was hoping to get the original one working though, as more of a novelty than anything because the actual maps wouldn't be very useful now. I also can't stop trying to fix something once I've started, which some say is a character flaw and others call being an engineer.

[pj8708]

If you can fix your problem you may be able to update the navigation software to current release date.

Paul

[1990LS400]

The final map update for the generation 1 navigation system was released in 2004.

[MayorofEastCtown]

Solved! It's been many moons since I posted this, but I finally had time (and money) to put into this. I ended up buying a new Nav computer, the one in the trunk, off Ebay for $50. For some reason no one is buying them anymore, so the price has plummeted. Just went back swapped them out and it worked. Sadly the unit I had, and the one I bought, didn't have Nav hard drives, so the nav doesn't work but everything else does. As far as what went wrong in the nav unit I'll never know, because sadly it was promptly thrown out by someone who thought it looked like trash and didn't want it in their house. Thanks again for all the help! 

[Tom Tone]

Recently my GPS on my 1998 GS400 stopped working.  It says "check hard drive".  I think that drive is located in the glove box, but the only thing I can find is the 6-CD changer.  Is there some other spot to find it?

[1990LS400]

44 minutes ago, Tom Tone said:

Recently my GPS on my 1998 GS400 stopped working.  It says "check hard drive".  I think that drive is located in the glove box, but the only thing I can find is the 6-CD changer.  Is there some other spot to find it?

The parts diagram shows the navigation hard drive as being on the right (passenger) side of the trunk.  I'm not very familiar with the GS but on the 1998-2000 LS400 like I had, the navigation hard drive was under a false floor on the right side of the trunk along with the ECU for the factory installed telephone system.