Turbo Express screen is waaaay too white = change the batteries :)

[Platinumfungi]

Update -Turns out it was just dying batteries   Thanks again for the help everyone!
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So I'm working on resurrecting a poor Turbo Express that was D.O.A. The fuse was blown, and it looks like someone was doing a small amount of tinkering around at some point - there was a massive solder blob that bridged some components, but luckily the traces connected those particular components anyway, so hopefully that didn't affect much.

Once the unit decided to boot up again, the screen was really washed out/way too bright/mostly white. No biggie, just the caps I thought. Unfortunately even after replacing all 17 of the standard surface mount electrolytic caps, the screen is still washed out/way too bright/mostly white. If I tilt the top of the unit towards me, I can see the screen more clearly, but that's a major pain to have to do.

The brightness pot seems to affects the screen just a little, but hardly anything at all compared to what it should. I tested the pot, and it's good. All solder connections look good to.

Seems like whatever this screen has going on wasn't affected by installing all new caps  

Anyone ever run across this issue, or have any ideas? My brain is pretty tired, so I thought I'd recruit more  

Thanks for any thoughts!

[grahf]

When you said "all net caps", do you mean ALL? If it's not that, there is a chance it's just the screen itself. Out of all the GT/Expresses I've had, there was some noticeable difference between the screens. Usually adjusting it fixes it though...

I would try:
-Letting the thing run for an hour or so. Sometimes it will "wake up" an old lcd.
-Put a brand new set of batteries in it.
-Try running it on AC power.

[Platinumfungi]

Thanks for the fast reply Grahf  I'll try your suggestions and see if anything changes. Interestingly enough, just having the unit sitting here powered on for maybe 5 minutes appears to be helping.

Ah, good call. When I said "all",  I just meant the 17 surface mount electrolytic caps, plus the one on the controller board. I have yet to ever go after the tiny smd ceramic ones...I hope I don't have to 

I unfortunately don't have a wall wart for these, this further clarifies that I need one. Perhaps over to the marketplace I go!

[Duo_R]

Did you try another screen?

[Platinumfungi]

Did you try another screen?

Unfortunately the only other unit I have here at the moment is faulty as well. I just tried hooking the screen from it to this unit I'm currently working on, and now all my batteries are about shot so the screen is so dark I can't really tell if the brightness dial is working 

Ok, me thinks I shall wait till I get the AC adapter (hopefully on Monday) to proceed further on this.

Thanks for the quick reply guys! I'll update this just as soon as I can test with the AC adapter.

[Charlie]

So I assume the contrast control isn't working?

Charlie

[turbokon]

I had a TE a while back with the exact opposite issue to yours, it was dark. I replaced most of the caps but didn't help. However when I took that screen and put it in another working TE, it worked.  If it's anything like mine, it might because something failed in the PCB. I got rid of the TE a few months back though.

[grahf]

I wouldn't bother with the smd caps since those generally don't fail. Even though your other express is also not working, I would try it's screen. Good luck.

[Platinumfungi]

Well after testing with my new AC adapter it's working just fine... So...yay I guess. I'm still wondering what was going on though.

Tomorrow I'm going to test it further with some batteries that I'm charging up to see if the screen is still washed out. I'll update at that point.

Thanks for the replies everyone. I really appreciate the help  


Charlie - I couldn't actually tell if it was working or not. Once I hooked it up with this new adapter it's working just fine though...

EDIT: I did hook up another screen as you all suggested too 

[Necromancer]

Isn't a washed out, overly bright screen always what happens with dying batteries?

[nat]

Yes, and it's also what happens with 99.9% of rechargeable batteries, even at full charge.

The fact that Red Ghost mentioned charging batteries makes me wonder if that's all he's tested as far as batteries go.

[Platinumfungi]

Yep. Batteries were the only problem. I use rechargeable ones all the time and never had a problem till now - I dug out some that I hadn't used in ages...and apparently they were just almost dead/not holding a charge.

As far as I knew the screen went dark, not light, when the batteries were almost dead. I guess I've never used batteries that were almost dead. Good to know! Due to all the others issues with this system, (read frustration) I just assumed it had to be some additional time consuming complication. Glad it wasn't 

Thanks for all the help everyone  I appreciate it. I'll change the topic title to reflect the result.

[grahf]

Well, at least you replaced all the caps

[Duo_R]

Ni-mh batteries work just fine. Nickel cadmiums are the ones that were the problem.