COMMON ,MAYBE IN THE EQUATORIAL ZONE, neither of my two passats have ever done that ,even up north here when it has been over those temps

 

Yes, very common, as a search will show. I haven't seen any solutions proposed, other than a very expensive replacement, which might also
fail with time. Mine gets a bit worse as time goes on.

 

LCDs just do that. There's no avoiding it.

 

There's no avoiding it if you bought a VW.

With proper design and materials, and LCD's do just fine at the temperatures which these fail (less than 90F). In fact, these worked perfectly for years, even when left in the sun in very hot conditions, then started going bad. It seems to be a problem with the backlighting, but could also be a problem with the temperature compensation of the LCD drive voltage. And, by the way, I've designed LCD drivers (integrated circuits) for many applications.

 

Mine tends to fade from the top down. In this heat, I wish the temperature reading would fade out. I find it just makes me even more depressed...

 

Mine tends to fade from the top down.

x2. I notice it when it's 88 degrees or hotter, and the car has been parked in the sun. Seems to work fine though. I have an '02 B5.5.

 

Nice to have a really informed perspective.

An attofarad isn't a hell of a lot. Where can that little capacitance possibly be useful?

 

When detecting the position of MEMS (micro electro-mechanical systems). Resolution maybe in single-digit attofarads.

 

yes it happens as mentioned above and above the above but the best is to get the windows tinted and get a sunshade for the windshield

 

Yes.

 

Are we talking about the big red display in the middle?
Isn't that LED not LCD? I'm under the impression monochrome LCD's are the displays that look like digital watches, the odometer, and the clock.

 

I was also making that assumption, until someone referred to it as an LCD. It probably is, since an LED array would be much more expensive.

LCD's can be backlit, so take on the color of the lighting (or whitish light plus colored filter). LCD segments can be black when "on"/clear when "off" (as is most common, like on the clock and radio), or can be black when "off" and clear when "on." That would be the case in the display we are discussing. The black or clear is controlled by having two polarizers, one behind and one in front of the LCD. When the segments are "on", the polarized light is rotated 90 degrees by the liquid crystal fluid in the display. If the polarizers are 90 degrees to each other, off segments will be black, and "on" segments will be clear (red with backlight in this case). If the polarizers are aligned, "off" segments will be clear (red ) and "on" segments will be black or nearly so.

I'm suspecting that something gets funky with the backlight. Backlights are often LEDs, which lose brightness with time, especially when used at high brightness levels.

Here are some examples of positive and negative displays:
http://www.crystalfontz.com/products/634/index.html

Or maybe they are really LED's

 

Fading...

Yes... Apparently this is an all too common problem --- and mine doesnt just fade, it goes COMPLETELY OUT!! Whenever the temp gets warm (about 80 degrees) it goes out. I live in south central Texas... and its almost always over 90 here during the day, and high 70s at nite. So, I have just learned to live without the display during the summer --- and just hope it comes back during the winter (when the temp drops into the 50s-60s). Considered replacing the whole instrument cluster till I realized (thru PW) that this is just the way it is... and I have tinted windows and use a sunshade for the windshield --- nothing helps!

In fact, the sun/heat here has claimed another victim... my rear view mirror... it always "droops" from the sun/heat. I got pissed at it yesterday while driving home and got too aggressive while "adjusting" it. Somehow the retaining ring fell off, the mirror got cracked, the elbow came off the windshield --- and now its all just sitting in the backseat of the Passat. :thumbdown

 

No problems with mine, but I've noticed something cool when I am wearing polarized sunglasses.

If I turn my head one way, the clock and odometer dissapear. Turn my head the other way, the digital readout disappears. Freaky, but cool.

 

No problems with mine either.

As for Polarized sunglasses, I had a set that were polarized in the wrong diriection! I could not see the readouts with my right eye. I had to return them for new lenses.

 

2001.5 b5.5 variant -- no problems with mine. I'm in San Antonio, and it hasn't gotten too hot here this summer, just a bit over 100 degrees, but the red bits are as red as they should be and the black parts are as black as they should be. I think this problem is very common on German cars in general, but I know it's notorious on Mercedes models, especially E and CLK class. Perhaps they use the same components or manufacturing techniques?

 

My 2000 does it too. When the temp hits the upper 80's, it starts to fade from the top down. At 105 (hottest day this year), almost the whole first line was gone.

STRANGE: When my ABS module failed, the display was dimmer overall, AND fading from the top - even though it was cold.

 

My 2001 sucks too, and it seems to be getting worse. In Missouri after a hot day on the lot, its completely gone. It starts to come back by the time I commute home with the A/C on. Too bad someone doesn't make a aftermarket or VW make a replacement that is LCD based vs LED. The radio LCD display still works fine when its hot.

 

It is LCD.

 

Haven't noticed it on our 2001 B5, and we live in FL. But the car is garaged most of the time, and when it is parked outside my wife has this gigantic silver sunshade she uses. When she has to go to the office (no covered parking), she always parks the car facing east or north if there is no shadetree available, so the strong afternoon sun hits the back of the car directly as opposed to beating down on the dashboard. The rear screen on the back window glass stays up pretty much year around.

Don't know how much these things help, but figure they can't hurt.

 

Wear polarized sunglasses then look at the LCD display on the back of your digital camera.

 

2000 year model with 100k and bright as ever

 

Hell it never gets hot in Minnesota! :lol:

 

Ya sure keep believing that. I measure my inside temp one day and it was like 120 inside

 

mines does it right in the middle of the LCD but when i got the A/C on it goes back to normal

 

If the polarizers were set at 90 degree difference, then you'd always be getting glare in one lens.

If you have a pair that's busted, take the lenses out, hold them up to a light source, then rotate one until the image is nearly black.

 

It was over 100 outside today and my read out was working fine.
I did have to use my polarized sun glasses and noticed the disappearing effect when I tilted my head.

 

Yes mine was fading in the heat at 30k miles and the dealer changed it under b2b warranty without queston along with a lot of other things like both headlight assy's (due to small cracks in the lenses).

 

My display also fades when it is dark. Has anyone thought of using a can of air, aka. computer dust off, turned upside down and spray on the display. The cold air may be enough to brighten the display. I don't have a spare can so could someone else try this and let me know?

 

i would assume that would not work, for the big plastic shield in front of all the gauges and stuff.

not only have i noticed my display to fade out in extreme sun, i've also noticed it "lag" in extreme cold. (ok, so in GA, 20° outside is extreme cold...) BUT most all LCD's will do that (even if i leave the cell phone in the car overnight in the cold - it'll act slow too)

 

02 1.8T...Mine fades...I have it set on Miles to Empty all the time and on 90 degree + days I get in the car and that part is unreadable but the temp and gear selection are fine...It comes back with the a/c ice cold after about an hour of driving around...On cool/cold days its bright as new...

 

03 1.8T Mine is doing the same thing. It drives me crazy. I bought this car (certified used from vw dealer) 5 months ago with 40k miles. By this time I've had to replace: engine, turbo, bearings, stop lights switch, left fog lamp, headlight, sunroof (whole assembly). Now my car is shaking at idle and I have to replace the cluster. Nice...

NEVER VW AGAIN!!!