Navigation System On several occasions the cursor on my navigation screen has suddenly veered off in ramdom directions. For example, I would be going west on I-66 and all of a sudden the cursor would show that I was no longer on I-66 but on another road, or not even on a road, and going south or norhteast, or whatever. There seems to be no pattern to this aberation and it arises for no particular reason. Several times it has happened in heavy rainfall but other times in clear weather. It has always self corrected either overnight or in a day or so. Since they have not been able to duplicate the problem when I have brought it in for service they have not fixed anything and I am at a loss as to how to proceed.

voper coming up thru oil dipstick

If the rest of the radio is working ok it's probably just a software lockup. Disconnect the car battery for several seconds to reset it. Should work after that.

Could be mute controls for the telephone. The voice for the Navigation is adjusted separately from the radio volume. If any work was done on the vehicle, like a battery disconnect, then radio controls may need to be reset.

You need to toggle through the Menu to things like screen brightness for the Navigation.

You also have a speed sensitive radio and the volume controls could be affected by these settings.

My wife has the Lexus IS250 with Navigation and just this morning she tells me she wanted to raise the AC from Low to higher position, but that nothing on the Navigation screen is working. I tried what David mentions above, but the only fuse that had 15A on it was in xlnt condition. Any other suggestions? Dealer talks like $1500 and the system has always been mediocre at best. Thanks for any help.

does it have a fuse and if so ,,check that ..or take to an authorized repair facility to have it diagnosed..the navigation is operated through a gps system..

If Lexus can't fix this there is nothing anyone here can do for it. Anything that can be done needs the proper scanning and reprogramming equipment only Lexus has. Being that the car is new when enough people complain about this they will come up with a fix, Their may be a recall on it in the future. But for now your going to have to live with it or trade the car in. I know you did'nt want to hear this but but if some yahoo directs you wrong it will cost you hundreds just to get the programming back to the way it is today. Some navigation systems if you disconnect the battery you will have to go to the dealer to get them to reprogram it. Use lots of caution when guessing. New cars are not made for the average back yard mechanic to touch.

I've reads post here suggesting disconnecting the battery for one hour. Couldn't hurt to try it.

Also try ejecting the Navi Disk, inspecting it for any damage, wait a few minutes and reinserting. The disk contains not only the navigation Database, but also part of the operating system.

DO NOT TRY INSERTING A OLDER NAVI DISK OR ONE FROM ANOTHER VEHICLE, THAT COULD DESTROY THE NAVI UNIT!!

If you need a new Honda Navi Disk, order it direct at https://www.hondanavi.com/Hondadvdsales/naviorder.php

Good Luck

if you are referring to the factory navigation, it does not play dvd's only navigation disks

Installing the DVD Map Disc Your dealer/retailer may have installed the map DVD. If the map DVD was not installed, do the following to load it:
Read the following steps completely.

1. Turn the ignition on. The vehicle must be in P (Park) to perform this operation.
2. Press (power) to turn the navigation system on.
3. Press the NAV hard key.
4. Touch the Insert Map Disc screen button. The screen opens to access the map DVD slot.
5. Load the map DVD partway into the slot. The system pulls it in. The screen cannot be closed until a double beep is heard.
   Notice: Pressing directly on the navigation screen may cause damage. Repairs would not be covered by the vehicle's warranty. Do not press directly on the navigation screen.
   
6. To close the screen, slightly push up on the two outer corners until the screen is in position. Then push the screen in by pushing on the four outer corners until a click is heard.
7. Set the search area. See "Setting the Search Area" earlier in this section.

Ejecting the DVD Map Disc The navigation portion of the system cannot be used if the DVD map disc is not loaded.

1. Press the MENU key to enter the Menu options, then press the MENU key repeatedly until Nav is selected or touch the Nav screen button.
2. Touch the Map Database Information screen button.
3. Touch the Eject Map Disc screen button. The screen tilts, exposing the map DVD slot.
4. Press the eject button, located next to the DVD map disc slot, and the disc ejects. Pull the disc out. The screen cannot be closed until a double beep is heard.
   Notice: Pressing directly on the navigation screen may cause damage. Repairs would not be covered by the vehicle's warranty. Do not press directly on the navigation screen.
   
5. To close the screen, slightly push up on the two outer corners until the screen is in position. Then push the screen in by pushing on the four outer corners until a click is heard.

sometimes the previous owner might wrote it down on the owners manual but if not then you need to pull the radio out and get the serial number and call the dealer they will give you a code