Just bought an 04 Lexus Ls 430 and the navigation system sometimes tells me that the external system not connected and the a/c controls don't function and the screen goes black for a couple of minutes and sometimes it works fine. Can somebody please tell me what i should do before i get charge couple of thousand $$? thank you in advance.

 

I would check the connections if you a comfortable at pulling trim

 

hello and thanks for replying, do you mean on the screen?

 

yes- but there could be other connections within the system. Maybe a shop manual would be something useful. Intermitent problems sometimes point to bad connections.

 

Yes, you are wright the only thing i tried was disconnecting the sockets from the navigation system located in the trunk but there was no solution, the wierd part is that sometimes if i turn off the engine and turn it back on it works again, i don't know if you have any other suggestions? thank you in advance.

 

Sorry buddy- I don't have any other suggestions. I would buy a shop manual if you don't want to pay the dealers crazy costs.

 

hey, thanks a lot for your help and tips. have a great day!!

 

Well it was raining today here in Ohio and I grabbed the umbrella from the backseat. Unfortunately I forgot to close the rear door all the way, so when I came out to my car today the battery was dead enough it wouldn't start.

Got a jump from a guy at work, and after I let her run for a while I got the dreaded "External System is not available".

Shut the car off for a while, restarted it, same thing. Symptoms: No Audio, NAV, HVAC controls, bluetooth, etc.

Got it home, checked all the fuses, still nothing.

*THE FIX THAT WORKED FOR ME*

Disconnected the positive battery terminal for about 5 minutes.
Reconnected it, and everything came back!

 

my Toyota Sienna has a nav system (JBL factory) that would do something similar. I learned that one of the fuses had a poor connection. I replaced all the radio/nav fuses and it works fine without interruption now. It's not expensive to try this fix too.

 

​​​​​​Did anyone figure out a solution? My 2004 does that every now and then. Seems to happen when I drive at highway speeds for a while