DVD Player Mitsubishi BD48DVD Service Documentation / CircuitDiagrams
 

Hi All.

My Dad has a Mitsubishi BD48DVD DVD player that is not working.

When a DVD is inserted it may function for a few seconds to a few
minutes before it re-starts the DVD play.
It will re-start the DVD over and over.
Then it will switch itself off.
Naturally, I have tried various DVDs.
The video output from the player will operate for the aforementioned
period of time and then freeze. It may then either jump forward by
several seconds to several minutes and continue for a brief time and
then re-start or it may re-start after the first 'freeze'.
It can also, sometimes, take a long, long time to load the DVD after
insertion.

I took the covers off to
(1) Clean the laser lens
(2) Take a look at the mechanical operation of the DVD section of the
device

Cleaning made no difference.

The disk spins-up fine and continues spinning during the fault
condition.
Before a DVD was inserted, I moved the lens towards the outside of the
DVD area and this returned home without any apparent difficulty when a
DVD was inserted.

I did notice that, when the fault condition ocurred, the power LED
indicator on the front panel began to flicker. This flickering does
not happen during 'normal' operation.
In addition, there is a barely audible but distinct 'clicking' sound
that seems to come from the DVD player section of the unit when the
fault condition exists. This 'clicking' would seem to be at the same
frequency as the LED flicker and is not audible when the unit operates
normally.

One possibility that ocurrs to me is that the PSU, or a section of it,
is failing. This failing section may not be able to supply enough
current and/or voltage for a particular section of the unit and this
may be the cause of the problems.
Of course, there may be a fault that causes more current to be drawn
from the PSU than that section of the PSU can supply.

I cannot find any technical documentation for this unit on the web.

Does anyone know where I might be able to get diagrams or other
information that would allow me to test?

Thank you for any help you may be able to provide.

Mike

DVD Player Mitsubishi BD48DVD Service Documentation / Circuit Diagrams
 

"AC Me" wrote in message
...
Hi All.

My Dad has a Mitsubishi BD48DVD DVD player that is not working.

When a DVD is inserted it may function for a few seconds to a few
minutes before it re-starts the DVD play.
It will re-start the DVD over and over.
Then it will switch itself off.
Naturally, I have tried various DVDs.
The video output from the player will operate for the aforementioned
period of time and then freeze. It may then either jump forward by
several seconds to several minutes and continue for a brief time and
then re-start or it may re-start after the first 'freeze'.
It can also, sometimes, take a long, long time to load the DVD after
insertion.

I took the covers off to
(1) Clean the laser lens
(2) Take a look at the mechanical operation of the DVD section of the
device

Cleaning made no difference.

The disk spins-up fine and continues spinning during the fault
condition.
Before a DVD was inserted, I moved the lens towards the outside of the
DVD area and this returned home without any apparent difficulty when a
DVD was inserted.

I did notice that, when the fault condition ocurred, the power LED
indicator on the front panel began to flicker. This flickering does
not happen during 'normal' operation.
In addition, there is a barely audible but distinct 'clicking' sound
that seems to come from the DVD player section of the unit when the
fault condition exists. This 'clicking' would seem to be at the same
frequency as the LED flicker and is not audible when the unit operates
normally.

One possibility that ocurrs to me is that the PSU, or a section of it,
is failing. This failing section may not be able to supply enough
current and/or voltage for a particular section of the unit and this
may be the cause of the problems.
Of course, there may be a fault that causes more current to be drawn
from the PSU than that section of the PSU can supply.

I cannot find any technical documentation for this unit on the web.

Does anyone know where I might be able to get diagrams or other
information that would allow me to test?

Thank you for any help you may be able to provide.

Mike



From your symptom I don't see any way to tell for sure if it's the laser,
the mechanism, or the DVD main board.

For example, I have seen SRAM chips cause similar symptoms, perhaps playing
a DVD with no or limited menus, and not the more common types with full
menus.

I have seen mechanical problems where the sled (stepper) motor hangs,
sometimes due to contamination like hair or carpet fiber.

A common failure mode for DVD lasers is to play a while, then start to
pause, pixelize, stop, etc. Often after about 30 minutes or so playing time.

With the flickering of the LED there may be a power supply problem - bad
caps or some such.

These days, troubleshooting DVD players is rarely economical. Easier and
cheaper to replace.


Mark Z.

DVD Player Mitsubishi BD48DVD Service Documentation / CircuitDiagrams
 

On Jan 9, 12:31*pm, "Mark Zacharias"
wrote:
"AC Me" wrote in message

...



Hi All.

My Dad has a Mitsubishi BD48DVD DVD player that is not working.

When a DVD is inserted it may function for a few seconds to a few
minutes before it re-starts the DVD play.
It will re-start the DVD over and over.
Then it will switch itself off.
Naturally, I have tried various DVDs.
The video output from the player will operate for the aforementioned
period of time and then freeze. It may then either jump forward by
several seconds to several minutes and continue for a brief time and
then re-start or it may re-start after the first 'freeze'.
It can also, sometimes, take a long, long time to load the DVD after
insertion.

I took the covers off to
(1) Clean the laser lens
(2) Take a look at the mechanical operation of the DVD section of the
device

Cleaning made no difference.

The disk spins-up fine and continues spinning during the fault
condition.
Before a DVD was inserted, I moved the lens towards the outside of the
DVD area and this returned home without any apparent difficulty when a
DVD was inserted.

I did notice that, when the fault condition ocurred, the power LED
indicator on the front panel began to flicker. This flickering does
not happen during 'normal' operation.
In addition, there is a barely audible but distinct 'clicking' sound
that seems to come from the DVD player section of the unit when the
fault condition exists. This 'clicking' would seem to be at the same
frequency as the LED flicker and is not audible when the unit operates
normally.

One possibility that ocurrs to me is that the PSU, or a section of it,
is failing. This failing section may not be able to supply enough
current and/or voltage for a particular section of the unit and this
may be the cause of the problems.
Of course, there may be a fault that causes more current to be drawn
from the PSU than that section of the PSU can supply.

I cannot find any technical documentation for this unit on the web.

Does anyone know where I might be able to get diagrams or other
information that would allow me to test?

Thank you for any help you may be able to provide.

Mike

From your symptom I don't see any way to tell for sure if it's the laser,
the mechanism, or the DVD main board.

For example, I have seen SRAM chips cause similar symptoms, perhaps playing
a DVD with no or limited menus, and not the more common types with full
menus.

I have seen mechanical problems where the sled (stepper) motor hangs,
sometimes due to contamination like hair or carpet fiber.

A common failure mode for DVD lasers is to play a while, then start to
pause, pixelize, stop, etc. Often after about 30 minutes or so playing time.

With the flickering of the LED there may be a power supply problem - bad
caps or some such.

These days, troubleshooting DVD players is rarely economical. Easier and
cheaper to replace.

Mark Z.

It would certainly be more cost effective to replace the DVD player if
I had
to take it to a specialist repairer.
Wouldn't it be a pity, though, to have to replace an item that just
had a
defective capacitor? It wouldn't be as friendly to our environment
either.
The real cost would be my time.

The real pity for efforts like mine is the lack of suitable
information to allow
even simple fault finding.

Take care.

Mike