Mitsu CS27303

[Tom Knowles]

Original complaint,, No Sound.
Now turning set on get good picture but still no sound. Pushing Menu
button on the remote turns the screen blue and nothing else works. Menu
button will restore it to it's original condition.
ONce in a while after unplugging the set and leaving it for day or so
it will work perfectly, until menu is pushed then all I get is the blue
screen.
I have read many FAQ'S about many caps being bad in these sets,
should I get busy with my ESR meter or should I look at the Micro
Processor circuits.
When it comes on in its "no sound" condition there is no OSD, but a
good picture , and the channels can be changed.
Since this tv is a 1994 model,is it ready for the landfill, or has
someone out there run into this before. Any suggestions will be
appreciated.
Thank you for taking your time to read this.
TOM

 

[inti2]

Original complaint,, No Sound.
Now turning set on get good picture but still no sound. Pushing Menu
button on the remote turns the screen blue and nothing else works. Menu
button will restore it to it's original condition.
ONce in a while after unplugging the set and leaving it for day or so
it will work perfectly, until menu is pushed then all I get is the blue
screen.
I have read many FAQ'S about many caps being bad in these sets,
should I get busy with my ESR meter or should I look at the Micro
Processor circuits.
When it comes on in its "no sound" condition there is no OSD, but a
good picture , and the channels can be changed.

Ahaha, the uP power supply has ripple in this moment ? Change the
electrolytic cap(s) that filter this line (5V) without testing them. If
you don't solve, check the dialog on the I2C channel... if you don't
solve... change the EEPROM... at the moment i haven't other ideas...

I.

Since this tv is a 1994 model,is it ready for the landfill, or has
someone out there run into this before. Any suggestions will be

No, it isn't ready for the landfill ! Probably it can be repaired for a
little price...

I.

 

[Leonard Caillouet]

On any sets that have a history of capacitor leakage, like this one, ESR
testing will not solve the problems alone. You have to find the caps with
electrolyte leakage, clean the board thoroughly, and repair any damaged
traces and joints. There are several ways to find these caps.

1. visually, look for dark goo on the negative legs of the caps
2. aromatically, heat the legs and smell for rotten fish
3. visually, look for "powdery" solder joints on the negative leg comared to
the positive leg
4. visually, look for spots on the board surrounding the cap that look wet
5. visually, look for black goo and corrosion on the traces near caps

ESR testing will often not identify a physically leaky cap. There may well
be several high ESR caps at this age and likely suspects such as the caps in
the power supplies and vertical circuits need to be checked for ESR for
sure, but looking for leakage is essential if you don't want to be fixing
the set repeatedly or chasing your tail.

Expect 10-30 bad caps in this model, not including the PIP module.

Leonard