GPS/Nav Help needed!!!

Just installed my stock GPS unit back into my 2005 SC430 after replacing the screen with a brand new one. The GPS unit was working perfectly before I removed it but was just hard to read the screen. Now that it is back in the car it does not work at all. It won’t light up, the door won’t open or close with power, (but I can move it by hand) there is no activity at all, seems brain dead.

I started thinking that maybe there was a blown fuse somewhere in the system.

To test this, I borrowed a GPS/Nav unit from my buddy who also has a SC430 (just a 2006 vs my 2005). His unit is also in perfect working order as it was when we removed it from his car. When I installed his unit in my car it did not work…just like my unit doesn’t work.

Now I’m thinking I have a blown fuse somewhere.

Here is the weird part. When we re-installed his unit back in his car it no longer works. The screen shows the logo page, but the buttons don’t activate it to open or close, no touchscreen or anything else. This unit was not altered in any way. It was just removed from one vehicle and installed into a different vehicle of the same type.

And when we tried my unit in his car it did not work either. So basically, they are both doing the same thing after being removed and re-installed. Non-working units now but fully functioning before. Two different units in two different cars doing the same thing after being simply taken out and then re-installed.

WHAT’S UP WITH THIS? IS THERE SOME CODE THAT NEEDS TO BE ENTERED TO MAKE THESE UNITS WORK AFTER THEY HAVE BEEN REMOVED?

This is so strange.

 

Given the weird situation of both going dead, a couple of questions to start this off.

Did you check to see if the build dates supported both years having the same part number for the display - it was during this time period that they made a change (both 5 speed or both 6 speed automatics)?

Connections:
Was anything other than the Climate control panel and multi-display unit removed, i.e., radio? The radio controls a lot of stuff including commends to Nav and amp, still working?

The first thing the FSM address about the door not functioning is the connection to the climate panel. You sure you got all the connections snapped in and securely reattached?

 

Jackhammer,
Which unit are we talking about? I assume you’re talking about the control unit, not a DVD in the trunk
My suggestions;
1. Check the fuse or the ECU
2. Double check the connections.
3. Install the old unit back
4. Pop the DVD and reinstall
You might crossed wires and blew the fuse.

 

All connections to climate panel are secure....

 

No wires to cross, everything is wired into plugs.
Keep 'em coming, we have got to figure this out!

 

In post #4 you state radio not hooked up. The nav door won't work without the radio in place unless you take other steps to replace the radio's function as the LAN master. A fellow forum member @khuong outlined that method in a thread I started (Audio System Makeover - ClubLexus - Lexus Forum Discussion). Nothing else will work either as the LAN connections to the navigation DVD drive and amplifier go through the radio.

Stuck in a pic from the FSM to show you what I mean

 

Don't want to be negative, but if you possibly shorted out or broke a wire somewhere in removal and then when you reconnected the unit is it possible that you fried the unit; and when you tried your friends unit it shorted out his unit too,,,,not a good thought but a possibility?