Mitsubishi WD-65731 DLP HDTV (V33 chassis)

[PlainBill]

I'm looking for advice on a recurring problem with our Mutsibishi
WD-65731. It was purchased about 18 months ago and had been very
reliable until earlier this year. At that time we started seeing the
'The TV will shut down in a few seconds. Make sure the air flow is
not blocked...' message. A little research indicated the problem was
an incorrect connector for a thermistor and was covered even though
the warranty had expired. A phone call brought a technician out
within hours and the set was repaired.

About two weeks later another problem cropped up, and I have found
only one reference to a similar problem. No resolution was given.

After the set has been on for an hour or more the brightness will
start flickering, followed a few minutes later by the colors dropping
out. If I had to describe the problem, I would say that the controller
for the DLP chip was not getting synchronization information from the
color wheel. Within 10 minutes I will have a picture composed of
various shades of pale green. I have verified that it is not the
program source; it even shows up on the setup menus.

Other points: It is more likely to occur in the afternoon. This led
me to suspect it is temperature related. I moved the TV away from the
wall, checked there was no obstruction to the air flow and that the
fans appeared to be running. Saturday I turned it on at about 1:00
PM, it was still working perfectly when I shut it off at 8:00PM. The
problem did not reoccur Sunday or Monday. Today it occurred within an
hour of the TV being turned on.

Now for the questions. Has anyone had this problem?
Does anyone here have any experience with Mitsubishi DLP sets?
Is there an online forum that would be more likely to have such a
person?
Taking a pessimistic approach, it is likely to be a problem with the
light engine. Is anyone willing to guess how much it will cost to
replace it?

Thanks,

PlainBill

 

[PlainBill]

Bill --

Many people have had this problem - so many infact -- that Mitsu sent
out a note that showed distributors how to fix this & extended the
warranty. The problem is that a little, badly designed connector near
the back of the set by the lightsource, wiggle loose randonly &
results in the screen message you see.

This does not normally get better by itself.

The simple fix is to open up the back of the set, pull out the
lightsource and its cage, and then clip the connector out of the
circuit, soldering in a couple of 4" long spacer wires.

This is easy to do in a 1/2 hour; otherwise you can try to get someone
to come in & fix it.

Go to these forums:
http://forums.cnet.com/5208-7596_102-0.html?forumID=60&threadID=233474&messageID=2412870

and read through the > 250 entries there. You'll get the benefit of
many other users trials & tribs w/ these sets.

Best, Tom

Tom,
Thank you for trying to help. However, that is old information.
According to the tech who REPAIRED my TV, the vendor who supplied the
thermistor assembly had used a connector designed for solid wire which
did not properly crimp to stranded wire. Mitsubishi has issued a
replacement part with the correct connector. Soldering is no longer
the appropriate solution.

I no longer get the air flow message, the TV does not spontaneously
shut down, all answers relating to the air flow thermistor are
incorrect. I only mentioned the old problem so nobody would propose
the wrong solution. I'm sorry I misled anyone.

Currently I have a new problem. The set is displaying incorrect
colors. Rather than direct anyone to the earlier posting, it is
reprodued here.

After the set has been on for an hour or more the color intensity will
start flickering, followed a few minutes later by the colors dropping
out. If I had to describe the problem, I would say that the controller
for the DLP chip was not getting synchronization information from the
color wheel. Within 10 minutes I will have a picture composed of
various shades of pale green. I have verified that it is not the
program source; it even shows up on the setup menus.

Other points: It is more likely to occur in the afternoon. This led
me to suspect it is temperature related. I moved the TV away from the
wall, checked there was no obstruction to the air flow and that the
fans appeared to be running. Saturday I turned it on at about 1:00
PM, it was still working perfectly when I shut it off at 8:00PM. The
problem did not reoccur Sunday or Monday. Today it occurred within an
hour of the TV being turned on.

Now for the questions. Has anyone seen this problem?
Does anyone here have any experience with Mitsubishi DLP sets?
Is there an online forum that would be more likely to have such a
person?
Taking a pessimistic approach, it is likely to be a problem with the
light engine. Is anyone willing to guess how much it will cost to
replace it?

Thanks,

PlainBill

 

[PlainBill]

I have not seen that problem (yet). The most dense source of Mitsu DLP
problems and solutions that I've run across is the cnet forum
referenced above. I'd post this message there.

Best, Tom

Tom, thanks for the suggestion. I saw what appears to be the
description of the problem on the AVS forums. I haven't had any
response if he ever had it solved.

PlainBill