Mitsubishi VS-4504CA projection tv won't turn on...Help ?

[[email protected]]

I have a Mitsubishi VS-4504 CA projection tv that won't turn on .One of
the resistors on the power supply board was burnt , I replaced it but
it still won't work . Any one out there that might be able to help get
me in the right direction to try to fix this ?

 

[Meat Plow]

I have a Mitsubishi VS-4504 CA projection tv that won't turn on .One of
the resistors on the power supply board was burnt , I replaced it but it
still won't work . Any one out there that might be able to help get me in
the right direction to try to fix this ?

What experience do you have?

 

[[email protected]]

I don't have any experience with TV's .I was hoping to find a schematic
for it and try to follow that to see where the problem starts . Someone
told me to start by changing all the electrolytics on the power supply
board because it has a switching power supply and that the caps are the
usual problem .

 

[Homer J Simpson]

I don't have any experience with TV's .I was hoping to find a schematic
for it and try to follow that to see where the problem starts . Someone
told me to start by changing all the electrolytics on the power supply
board because it has a switching power supply and that the caps are the
usual problem .

Bad advice and not a good way to learn.

 

[Leonard Caillouet]

Bad advice and not a good way to learn.

Better advice would be to do some searching about V10 and V11 Mits chassis
electrolytic capacitors and change all of the BAD (mostly leaky, some high
ESR) ones on the major boards. You will find 30-60 of them in that set in
almost all cases.

Leonard

 

[Homer J Simpson]

Better advice would be to do some searching about V10 and V11 Mits chassis
electrolytic capacitors and change all of the BAD (mostly leaky, some high
ESR) ones on the major boards. You will find 30-60 of them in that set in
almost all cases.

Based on his comments I figure he is staring disappointment in the face.
ISTM an ESR meter is essential for this repair.

 

[Leonard Caillouet]

Based on his comments I figure he is staring disappointment in the face.
ISTM an ESR meter is essential for this repair.

Actually, the need for an ESR meter on these is overstated. Nearly all the
leaky caps have to be identified physically and test fine for ESR. Only the
ones in the PS will usually have high ESR and not be leaky, then there are
usually only four that need to be changed there. We repair most V10 and V11
sets without needing ESR meters. We do test some key areas after replacing
the obviously bad caps but almost never find any more with the meter. ESR
meters are essential for the servicer in general, but a DIYer on these sets
does not need one in most cases. Mostly you need patience, diligence, a
keen eye and nose.

Leonard

 

[[email protected]]

I replaced R918 on the PS board ,it was totally burnt . The copper
trace was burnt bad right there aswell . Can anyone tell me if pin 3 of
IC900 connects to one end of R918 or just to J15 . I replaced C911 and
C917.I don't have a cap meter so I just tested them with my analog
meter and they didn't seem good.C965 and C963 test ok with my meter but
the outside plastic sleeves are slightly shrunken .C924 and C931 check
ok on a friends cap checker .What would cause R918 to burn ?Over
heating from IC900,over current,or should I be suspecting IC900 as bad
?If anyone could send me a copy of the PS board schematic by email that
would probably help me .And if you could tell me which actual caps are
the most likely to suspect that woulld be much appreciated .I know that
this TV is getting pretty old now . but it did work very good before
this happened and it woud be nice to get it going again.I'm trying to
do the best with my limited knowledge of TV circuitry .Thanks