Question about Sony GDM-W900 24" CRT Monitor

2 Answers

Sony GDM-W900 24" CRT - Intermittent flicker

Have a pair of these wonderful 24" CRT's here that have exhibited an unusual behavior. 95% of the time they are working terrific - excellent color, focus, brightness. But every so often, one or the other will do one or more of the following:

1) Get dim at the top of the screen and flicker that dimness, sometimes to the point where it reaches the bottom and blanks the whole display (only for fractions of a second) - this is the most common problem.

2) Displays a single horizontal rgb line in the lower third of the display but in no other way distorts the 1920x1200 output - less common but easiest to ignore.

3) Occasional high pitched whine (yes, this is almost certainly the flyback) - far less common, but very hard to ignore.

After a few hours these things disappear and it's back to being a fantastic monitor again. But the fact that it's intermittent makes it very hard to diagnose.

I have the full schematics and service manual for these beasts and I'm no stranger to replacing soldered components (and I'm well aware of how to discharge the HV caps). However I can't quite get my finger on what could be causing these issues.

I can pickup a replacement flyback for about $35, but I've no interest in spending the money if it turns out to be an IC somewhere else.

Any suggestions?

Posted by on

  • KHolden Dec 26, 2008

    >>I would suggest check weak caps and dry solder joints in deflection area.

    Well that narrows it down to about 400 caps :) I assume it would make the most sense to check the high voltage caps first yes? There are several 2kv and perhaps a dozen or so over 200v on the deflection board. Since I have to yank them to test for leakage, I'd hate to have to pull them all...


2 Answers

  • Level 2:

    An expert who has achieved level 2 by getting 100 points


    An expert who has answered 20 questions.


    An expert that has over 10 points.


    An expert whose answer got voted for 2 times.

  • Expert
  • 100 Answers

Resolder the junctions and points on the main board and check up for any faulty capacitors.also check for any short tracking occuring in the power section and repair the power supply points.

Posted on Dec 26, 2008

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 20 achievements.


    An expert that got 10 achievements.


    An expert that got 5 achievements.

  • Master
  • 10,594 Answers

I would suggest check weak caps and dry solder joints in deflection area.

Posted on Dec 26, 2008

  • Shahid Electronics
    Shahid Electronics Dec 26, 2008

    Please check electrolytic caps of 35 volts to 200 volts only
    As you know its bit older monitors of 1999 maybe so 10 years time is enough for caps to reduce capacitor's efficiency.


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

Monitor intermittent power problem and horizontal green flickering lines

separate wiring. touching wires creates cross-talk of signals.

Jan 28, 2014 | Computer Monitors

1 Answer

Pop - bang noise then went dead after a period of time

You've blown a capacitor and probably the horizontal output circuity. It's time to get a new LCD monitor.

May 30, 2009 | Sony GDM F520 21" CRT Monitor

1 Answer

Sony 24'' CRT widescreen GDM-FW900 blurry after initial on

CRT shorts are common with this model and focus problems are a major symptom. however, the loud 'pop' you described leads me to believe that the flyback transformer may have a problem in the focus divider portion. replace the flyback, if that fails then the CRT is most certainly the problem

Nov 20, 2008 | Sony GDM-W900 24" CRT Monitor

1 Answer

Display is off gray scale

I found it. I engaged expert mode in the OSD menu

Jul 31, 2008 | Sony GDM-90W11 24 in.CRT Conventional...

1 Answer


Is the orange flicker on the screen or on the button?

Does it always stay on or does it go off?

What kind of monitor is it? Flat screen LCD or CRT?

Mar 23, 2008 | Dell UltraSharp 1800FP 18.1" LCD Flat...

1 Answer

Screen always bleu

ok.. most probably the data cable of your monitor is damaged.. try to check it if the pins are still in tact.. if not, then you should replace it with new one..

Jan 20, 2008 | Sony GDM-400PS 19" CRT Monitor

1 Answer

Blank screen

You can get the unit repaired by emailing , he will call you if you provide your telephone number.

Jan 07, 2008 | IBM E54 (Pearl, White) 15 in.CRT...

1 Answer

Turns ON only after a day or so of rest.

I think you have a faulty Power Supply, more than likely it is gonna be my old favorite faulty Electrolytic Capacitors, Intermittent problems are real tricky to fix, If ya handy you could try opening it up and having a squiz, look for any loose connections or "Swollen" Capacitors see if all the "Lights" are on etc, try gently "Tapping" around maybe it's a "Dry Joint" but my money is on the PSU. If ya can see a problem say Faulty Electro's replace with the same or better Temperature rating ... Good luck

Jul 30, 2007 | SGI Silicon Graphics GDM 4011P 20" CRT...

Not finding what you are looking for?
Sony GDM-W900 24" CRT Monitor Logo

Related Topics:

105 people viewed this question

Ask a Question

Usually answered in minutes!

Top Sony Computer Monitors Experts

Cindy Wells

Level 3 Expert

4759 Answers

Lala Alonsi
Lala Alonsi

Level 2 Expert

56 Answers

ray gallant

Level 3 Expert

36432 Answers

Are you a Sony Computer Monitor Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides