Broken BENQ FP731 LCD Monitor

P

Powermac

Guest
Hello,

I have a BENQ FP731 monitor that does not work correctly and was
wondering if it is worth fixing.

When you turn it on the power light comes on, you see the momentary
BENQ logo flash (screen looks normal) and a second of video from the
computer and then the screen goes black. When the screen is black the
power light stays on and is green, if you turn off the computer it
goes into yellow standy. I asume the signal section is working, but
something is shutting down the LCD. If I turn it off and turn it back
on with the power button it does the same logo + 1sec of video then
black screen again.

Any ideas? Is this a common fix?
 
Powermac wrote:
On Jul 18, 10:15 pm, Powermac <teozen...@gmail.com> wrote:
Hello,

I have a BENQ FP731 monitor that does not work correctly and was
wondering if it is worth fixing.

When you turn it on the power light comes on, you see the momentary
BENQ logo flash (screen looks normal) and a second of video from the
computer and then the screen goes black. When the screen is black the
power light stays on and is green, if you turn off the computer it
goes into yellow standy. I asume the signal section is working, but
something is shutting down the LCD. If I turn it off and turn it back
on with the power button it does the same logo + 1sec of video then
black screen again.

Any ideas? Is this a common fix?

One other thing, I can see faint XP menu showing when I look at the
screen at specific angles so the backlight is just shut down I asume.


The HV inverter or the CFL tubes are going bad.


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sheep.
 
On Jul 18, 10:15 pm, Powermac <teozen...@gmail.com> wrote:
Hello,

I have a BENQ FP731 monitor that does not work correctly and was
wondering if it is worth fixing.

When you turn it on the power light comes on, you see the momentary
BENQ logo flash (screen looks normal) and a second of video from the
computer and then the screen goes black. When the screen is black the
power light stays on and is green, if you turn off the computer it
goes into yellow standy. I asume the signal section is working, but
something is shutting down the LCD. If I turn it off and turn it back
on with the power button it does the same logo + 1sec of video then
black screen again.

Any ideas? Is this a common fix?
One other thing, I can see faint XP menu showing when I look at the
screen at specific angles so the backlight is just shut down I asume.
 
These things come in my shop and its suprizing how many different
branded ones all have the same insides .

I just fixed 3 Proview monitors that did exactly what yours does . Each
monitor had a weak capacitor on the inverter board .

Others i see have had several bad capacitors in the power supply .
 
On Sat, 19 Jul 2008 18:00:42 -0600, goodguyy@webtv.net (Ken G.) wrote:

These things come in my shop and its suprizing how many different
branded ones all have the same insides .

I just fixed 3 Proview monitors that did exactly what yours does . Each
monitor had a weak capacitor on the inverter board .

Others i see have had several bad capacitors in the power supply .
couple of questions for this one.
I to have a benq with a back light problem and am <as a fun project>
trying to get it to work.
so I was wondering a: which caps should I be looking at that might be
faulty, and b: how to tell if it is in fact the back light that has
gone bad, and not the board. so I guess i am asking what the voltage
at the pin outs should be if the board is working, and the backlight
is not.
kallita
If you really want to talk to me - just eat the spam
 
On Jul 28, 3:31 pm, james moffat <kallispa...@shaw.ca> wrote:
On Sat, 19 Jul 2008 18:00:42 -0600, goodg...@webtv.net (Ken G.) wrote:
These things come in my shop and its suprizing how many different
branded ones all have the same insides .

I just fixed 3 Proview monitors that did exactly what yours does . Each
monitor had a weak capacitor on the inverter board .

Others i see have had several bad capacitors in the power supply .

couple of questions for this one.
I to have a benq with a back light problem and am <as a fun project
trying to get it to work.
so I was wondering a: which caps should I be looking at that might be
faulty, and b: how to tell if it is in fact the back light that has
gone bad, and not the board. so I guess i am asking what the voltage
at the pin outs should be if the board is working, and the backlight
is not.
kallita
If you really want to talk to me - just eat the spam
I fixed it, needed two shorted transisters replaced and a couple
capacitors.
 
On Sat, 2 Aug 2008 14:03:06 -0700 (PDT), Powermac
<teozenios@gmail.com> put finger to keyboard and composed:

I fixed it, needed two shorted transisters replaced and a couple
capacitors.
I had the same problem in a Dell monitor (rebadged Benq). It seems
that the 2SC5707 transistors are not an uncommon fault.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
 
On Sat, 2 Aug 2008 14:03:06 -0700 (PDT), Powermac
<teozenios@gmail.com> wrote:

On Jul 28, 3:31 pm, james moffat <kallispa...@shaw.ca> wrote:
On Sat, 19 Jul 2008 18:00:42 -0600, goodg...@webtv.net (Ken G.) wrote:
These things come in my shop and its suprizing how many different
branded ones all have the same insides .

I just fixed 3 Proview monitors that did exactly what yours does . Each
monitor had a weak capacitor on the inverter board .

Others i see have had several bad capacitors in the power supply .

couple of questions for this one.
I to have a benq with a back light problem and am <as a fun project
trying to get it to work.
so I was wondering a: which caps should I be looking at that might be
faulty, and b: how to tell if it is in fact the back light that has
gone bad, and not the board. so I guess i am asking what the voltage
at the pin outs should be if the board is working, and the backlight
is not.
kallita
If you really want to talk to me - just eat the spam

I fixed it, needed two shorted transisters replaced and a couple
capacitors.
Also need to redo cracked solder on the inverter transformers or the
transistors will blow again
 
On Aug 2, 9:10 pm, Franc Zabkar <fzab...@iinternode.on.net> wrote:
On Sat, 2 Aug 2008 14:03:06 -0700 (PDT), Powermac
teozen...@gmail.com> put finger to keyboard and composed:

I fixed it, needed two shorted transisters replaced and a couple
capacitors.

I had the same problem in a Dell monitor (rebadged Benq). It seems
that the 2SC5707 transistors are not an uncommon fault.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
As long as it outlasts the warrenty the manufacturers don't care it
seems about build quality.
 
On Wed, 17 Sep 2008 13:52:23 -0700 (PDT), Ash <ashstevens1@gmail.com>
put finger to keyboard and composed:

Do you have instruction and what capactors ( location and transitors
you changed and where to find them. I have the exact same problem and
want to fix it any help would be appriciated
Change the 2SC5707 transistors and electrolytic caps in the inverter
section. Also check the 3A picofuse, and resolder all transformer
pins.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
 
On Aug 2, 5:03 pm, Powermac <teozen...@gmail.com> wrote:
On Jul 28, 3:31 pm, james moffat <kallispa...@shaw.ca> wrote:





On Sat, 19 Jul 2008 18:00:42 -0600, goodg...@webtv.net (Ken G.) wrote:
These things come in my shop and its suprizing how many different
branded ones all have the same insides .

I just fixed 3 Proview monitors that did exactly what yours does . Each
monitor had a weak capacitor on the inverter board .

Others i see have had several bad capacitors in the power supply .

couple of questions for this one.
I to have a benq with a back light problem and am <as a fun project
trying to get it to work.
so I was wondering a: which caps should I be looking at that might be
faulty, and b: how to tell if it is in fact the back light that has
gone bad, and not the board. so I guess i am asking what the voltage
at the pin outs should be if the board is working, and the backlight
is not.
kallita
If you really want to talk to me - just eat the spam

I fixed it, needed two shorted transisters replaced and a couple
capacitors.- Hide quoted text -

- Show quoted text -
Do you have instruction and what capactors ( location and transitors
you changed and where to find them. I have the exact same problem and
want to fix it any help would be appriciated
 

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