Sony GDM-F500R (G1 Chassis) has trouble turning on
I got this monitor used five years ago. Since then it has always had
the overbrightness problem, but I scraped by with brightness set to 0
and contrast to 100. This was annonying, and the local service center
in India refused to service it. About a year back, it started
exhibiting a new problem -- it will not turn at all! The power LED
will turn on, but will flash in amber every 1.25 seconds. Turning it
on and off did nothing. So I put the monitor in cold storage. After
about a couple of months, curiosity got the better of me, and when I
plugged it in, it worked just fine. It worked for some more months,
and then mysteriously, refused to turn on one fine day. All I got is
that blinking amber light. In frustration/desperation, I pushed the
power button for about fifteen minutes, and it turned on. Everyday
since then, regardless of whether it was in standby mode or turned off
overnight, my daily morning ritual is to repeatedly push the power
button in order to turn my monitor on. Sometimes it takes a few
minutes, sometimes over couple of hours.
After some googling, I was able to download the schematic for it and
also got information on using WinDAS to adjust its G2 register to
correct the brightness problem. I build the necessary serial cable and
now the monitor is close to perfect (displaywise: G2 was set to 199, I
lowered it to 155), except for the power-on problem.
Here is some detailed information on how I get to turn my monitor on:
With 220V supply:
1. Turn the monitor on. If amber light flashes, go to #2, else it
turns on.
2. Turn it off. Wait for 5 sec (exact)
3. Repeat from 1.
With 110V Supply:
1. Turn the monitor on. If amber light flashes, go to #2, else it
turns on.
2. Turn it off. Wait for less than 1 sec.
3. Repeat from 1.
The interesting thing to note here is that when the monitor does
eventually turn on, it is preceded by the sounds of relay clicks. Once
the relays start clicking, it will not turn on right away, but after a
few more on-off cycles, it will. The moment I hear the first relay
click, I am relieved since I know the monitor will eventually turn on.
But I think the problem is getting worse, since my daily wait time is
getting longer.
I suspect some electrolytic capacitor has gone bad, but don't have an
ESR meter. I am going to build an ESR meter and go over all the
electrolytic capacitors inside.
Does anyone have better clue than me, or is it a well known problem?
Thanks.
the overbrightness problem, but I scraped by with brightness set to 0
and contrast to 100. This was annonying, and the local service center
in India refused to service it. About a year back, it started
exhibiting a new problem -- it will not turn at all! The power LED
will turn on, but will flash in amber every 1.25 seconds. Turning it
on and off did nothing. So I put the monitor in cold storage. After
about a couple of months, curiosity got the better of me, and when I
plugged it in, it worked just fine. It worked for some more months,
and then mysteriously, refused to turn on one fine day. All I got is
that blinking amber light. In frustration/desperation, I pushed the
power button for about fifteen minutes, and it turned on. Everyday
since then, regardless of whether it was in standby mode or turned off
overnight, my daily morning ritual is to repeatedly push the power
button in order to turn my monitor on. Sometimes it takes a few
minutes, sometimes over couple of hours.
After some googling, I was able to download the schematic for it and
also got information on using WinDAS to adjust its G2 register to
correct the brightness problem. I build the necessary serial cable and
now the monitor is close to perfect (displaywise: G2 was set to 199, I
lowered it to 155), except for the power-on problem.
Here is some detailed information on how I get to turn my monitor on:
With 220V supply:
1. Turn the monitor on. If amber light flashes, go to #2, else it
turns on.
2. Turn it off. Wait for 5 sec (exact)
3. Repeat from 1.
With 110V Supply:
1. Turn the monitor on. If amber light flashes, go to #2, else it
turns on.
2. Turn it off. Wait for less than 1 sec.
3. Repeat from 1.
The interesting thing to note here is that when the monitor does
eventually turn on, it is preceded by the sounds of relay clicks. Once
the relays start clicking, it will not turn on right away, but after a
few more on-off cycles, it will. The moment I hear the first relay
click, I am relieved since I know the monitor will eventually turn on.
But I think the problem is getting worse, since my daily wait time is
getting longer.
I suspect some electrolytic capacitor has gone bad, but don't have an
ESR meter. I am going to build an ESR meter and go over all the
electrolytic capacitors inside.
Does anyone have better clue than me, or is it a well known problem?
Thanks.
0
Comments
The thing that is unsettling to my inner geek is that the problem is probably very minor, like a $1 part. It would be shame to junk this machine, since I know it can be fixed. I'll probably end up spending quite some time trying to fix it, but the whole experience is sorta fun, and it feels like solving a really interesting puzzle.
Turns out that the problem was bad capacitors afters all. Five of them in the power supply. 100uF and 47uF variety. I think there were two more that were borderline cases, but I left them in for now. From the looks of it, and how they were all clustered, I think the 5V regulator section must have kept them hot over the years, specially since standby needs this part of the circuitry live all the time.
$0.18 repair saves a $1,800 monitor.