andynoel78

Hello,

I'm hoping to receive some help in solving a problem with the nav unit in my '11 GS450h.

For the past few days, every time i turn the car ON (with the headlights ON), the nav screen, clock and surrounding buttons illuminate as they should, but after ~3 seconds, the illumination for the surrounding buttons and clock shut off.

Also, the touch-screen functioning and surrounding buttons do not work at any time. The nav screen remains illuminated, however the touch-screen buttons and surrounding buttons do not work. If i turn the car off and restart, same thing; all lights illuminate for about 3 seconds then stop.

During the day with no lights on, the clock will illuminate for ~3 seconds, then shut off just like above. None of the surrounding buttons (climate, map, infom audio, display, etc) work at all.

What would cause this unusual condition? I feel like if a fuse were blown, it wouldn't work, period. But, the lights illuminate for a few seconds before shutting off.

The emergency flasher button works and illuminates always, and the passenger airbag lights do, likewise. I pulled the nav unit from the car and checked all cables, and they all appear in place.

I can communicate with the car via the voice commands, but that's it.

Any idea what might be causing these strange symptoms?

Thanks in advance!

IXI187IXI

iTrader: (3)

sounds like there is a short somewhere. did you go any work around the navi screen where you could be pinching a wire and its grounding out?

andynoel78

Actually, yes. Last week i changed out all the green LEDs in the nav unit to white ones. Simple mod, though, i've done it before without issue.

Would a short somewhere cause these symptoms? If it were a short, why would the buttons power up for 3 seconds then shut down?

IXI187IXI

iTrader: (3)

im thinking its a short, thats what it sounds like. might be getting enough power for 3 second then shorting out when it grounds itself out

andynoel78

You were right!

The circuit boards containing the switches for CLIMATE, AUDIO, etc. have a small metal tab on the back that needs to make contact with the metal housing behind it; that tab wasn't making good enough contact on the left side. Tightened some screws holding the circuit board in place, and everything works, now.

These cars are incredibly complex! Thanks for the help!

DrexLex

Happily you got it running, and happily, it was not a short. A short could cause permanent damage. What you had was an "open." A broken connection.

uberEJ

iTrader: (2)

wait how did you change the buttons illumination to white leds?

did you have to solder or are they just bulbs?

IXI187IXI

iTrader: (3)

.

andynoel78

Well, the radio buttons and nav surround buttons are all easily converted to white SMDs (a special type of LED) as they come stock with green SMDs; so all i needed to do was remove the green SMDs via a razor blade and solder on white SMDs of the same size.

However, things got way more difficult when converting the center console lights (P-R-N-D-S icons, cig lighter light, TRAC OFF, PWR HYBRID SNOW, SPORT NORMAL switches) to white SMDs as they come stock illuminating via small bulbs. As these bulbs are of a very rare size, there is nowhere in existence a plug n' play LED bulb to simply replace them with. I had to custom modify the lights by wiring "into" the switches two white SMDs (soldered in series) with the respective resistor to prevent them from burning out (as the stock bulbs were given 12V and the SMDs require about 3.2V and 20mA of current. It took me a whole day to just do those buttons!