Larry Dillon said:
ryo, leave an e-mail addres and i will send you what you need, And I have found if the 3.3 is missin usually there is a problem with the light engine. It is loading down that voltage.
Thanks for the suggestion. I'm looking at the 3.3V on the standby power supply. Looks like it's missing, but the IC's have the 12V.
Scourche said: For all you folks lucky enough to encounter this one. (Blinking Green LED). I have been repairing TV sets for close to 20 yrs. now. In my experience the Mitsu WD-52525 can be a real nightmare to fix. I have found that the blinking LED prob. is one of three things. Either you are missing one, or more supply voltages from the power supply, The Digital Module(DM) has bad filter caps, or the Formatter(FMT) Bd. has bad filter caps. I have found bad caps in many of these. you can usally tell them by the bulge on the top. The DM and the FMT Bd. each use four (1000uf) caps to filter the DC supplies to them. The blinking indicates that the system software is loading. If one of these Bds.is not getting it's correct supplies this routine does not complete. I have replaced caps and still come up with bad Bds. Not to mention the 100 screws you will have to remove just to get to them. SO if youre brave enough to take this one on, Know this...Mitsubishi has recently informed me that these modules are on nationwide back order for up 7 Months. GOOD LUCK.........
I am surprised at all the folks who are willing to do this kind of repair themselves, i'am a tech of 30yrs and was scared the first time i encountered these 525 repair, i would say for those who have no technical or soldering background they might make matters worse and render thier sets unrepairable, such electronics repair should be done by technically qualified persons, i do not condone the transfering of fix it info to persons who are known not qualified. At a Mitsubishi symposium hosted by/at the recent NPSC convention in Buffalo NY it was stated by the Mitsubishi rep that half of these modules when they finaly arrive to them they have major board damage and these are caused by "do it yourselfer" and do cause major return delays.
The reason many of us are trying to do the repair ourselves is that we have tried taking the set to certified techs and find out the repair is too expensive... My estimate was over 1K and the certified tech would not guarantee his work (too many known problems with the set). So after dragging the non-functional set home I had a choice, chop it up and throw it in the trash can or try to fix it myself. If my repair causes "major board damage" the end result is the same - $3500 into the garbage can...
Ryo_Ohki2,
I seem to be having a similar problem. I've replaced caps on the DM, FMT, and signal boards with no luck. On the power supply I do not measure 5V or 3.3V at the test points in the upper right corner. I have replaced the PWM Controller (IC9A21) and FET (Q9A20) with no luck.
Interesting comment from Larry about the light engine loading it. Will have to look into that.
sorry but they(mitsubishi), does not supply that a it is concidered not feild serivceable, tri state module can rebuild them or may have an exchange for it.
Thanks for your feedback, although I do agree with you about the difficuilty in epairing this line of tv set, I have had several NO, MANY folks who have repaired their DLP BY the info I have sullplied them but many who are unsucsesful Too!I myself have found many of these problem to be bad light engines along with a(part of the light engine called the DMD is the culprit). Again thanks for your input and feedack here at techlore.com just a note Mitsubishi dos not supply any service info on the light engine so. NO I cannot help all those who have asked for the schemtics or info on the DMD Board.
gslacker said:
Ryo_Ohki2,
I seem to be having a similar problem. I've replaced caps on the DM, FMT, and signal boards with no luck. On the power supply I do not measure 5V or 3.3V at the test points in the upper right corner. I have replaced the PWM Controller (IC9A21) and FET (Q9A20) with no luck.
Interesting comment from Larry about the light engine loading it. Will have to look into that.
Larry do you have schematics for this beast?
Oh man.. I don't know if your situation is the same with me, but with the POWER board not connected to anything, and not supply the voltage required for the DMD tells me it's definitely a issue in the POWER Board. After changing the PWM & FET, did you get that 3.3V coming out of the board? If so then it might be the DMD/Engine.
Larry, Where is the DMD board located? I'm not at home to look at my chassiss. Is it part of the whole module, or is it located somewhere else. If it's somewhere else, then I want to take a look at the DMD board to see if there's anything I reverse engineer and fix, assuming my POWER board fix is successful and the TV still doesn't work.
Okay.. Just tried turning on the POWER board to do some probing..
I heard this rapid clicking sound... Relay? I can't seem to reproduce it by cycling the power. Nuts.
Ryo_Ohki2 said: Oh man.. I don't know if your situation is the same with me, but with the POWER board not connected to anything, and not supply the voltage required for the DMD tells me it's definitely a issue in the POWER Board. After changing the PWM & FET, did you get that 3.3V coming out of the board? If so then it might be the DMD/Engine. Larry, Where is the DMD board located? I'm not at home to look at my chassiss. Is it part of the whole module, or is it located somewhere else. If it's somewhere else, then I want to take a look at the DMD board to see if there's anything I reverse engineer and fix, assuming my POWER board fix is successful and the TV still doesn't work. THanks
No change after replacing the PWM and FET, still no 3.3V in that area of the supply. I do have 3.3V in other areas, but not at the test points or connector PA. (I think its PA, I'm not home and can't look at it now to verify!)
The PA connector supplies power to the light engine according the diagram I have. Will look into the DMD/light engine this weekend.
Ryo_Ohki2 said: Oh man.. I don't know if your situation is the same with me, but with the POWER board not connected to anything, and not supply the voltage required for the DMD tells me it's definitely a issue in the POWER Board. After changing the PWM & FET, did you get that 3.3V coming out of the board? If so then it might be the DMD/Engine. Larry, Where is the DMD board located? I'm not at home to look at my chassiss. Is it part of the whole module, or is it located somewhere else. If it's somewhere else, then I want to take a look at the DMD board to see if there's anything I reverse engineer and fix, assuming my POWER board fix is successful and the TV still doesn't work. THanks
No change after replacing the PWM and FET, still no 3.3V in that area of the supply. I do have 3.3V in other areas, but not at the test points or connector PA. (I think its PA, I'm not home and can't look at it now to verify!)
The PA connector supplies power to the light engine according the diagram I have. Will look into the DMD/light engine this weekend.
What other areas did you get the 3.3V? Your right about the 3.3V going to PA connector. If the block diagram is correct, then 3.3V is suppose to be a standby voltage that should be going down the PA connector on pins 6 & 8. Maybe the DMD is working but not getting the voltages to it. Well at least that is my current thinking. Going to consult with one of my coworkers that does do TV repair as a side job.
I just talked with my coworker. He looked at the schematic off the datasheet for the IRU3037 and based on my voltage measurements, he's determine that this PWM controller is in shutdown mode. He is not sure if it's forced to shutdown mode by a different part of the circuit or if the IC is defective. This guy is sharp as nails.. 40years in design engineering, and 40+ years in repairing stuff.
Ryo_Ohki2 said: Oh man.. I don't know if your situation is the same with me, but with the POWER board not connected to anything, and not supply the voltage required for the DMD tells me it's definitely a issue in the POWER Board. After changing the PWM & FET, did you get that 3.3V coming out of the board? If so then it might be the DMD/Engine. Larry, Where is the DMD board located? I'm not at home to look at my chassiss. Is it part of the whole module, or is it located somewhere else. If it's somewhere else, then I want to take a look at the DMD board to see if there's anything I reverse engineer and fix, assuming my POWER board fix is successful and the TV still doesn't work. THanks
No change after replacing the PWM and FET, still no 3.3V in that area of the supply. I do have 3.3V in other areas, but not at the test points or connector PA. (I think its PA, I'm not home and can't look at it now to verify!) The PA connector supplies power to the light engine according the diagram I have. Will look into the DMD/light engine this weekend.
What other areas did you get the 3.3V? Your right about the 3.3V going to PA connector. If the block diagram is correct, then 3.3V is suppose to be a standby voltage that should be going down the PA connector on pins 6 & 8. Maybe the DMD is working but not getting the voltages to it. Well at least that is my current thinking. Going to consult with one of my coworkers that does do TV repair as a side job.
I would have to look at the board to give you exact locations, but there are some resistors in an area below and to the left of the PWM and FET, kind of the top left corner of the AC input stuff.
I agree the PWM could be in shutdown. One thing I've noticed on mine is pin 8 is ~0V. If its being used as a soft start feature in the design it should ramp up to a voltage at turn on. It could also be driven low by another circuit forcing it into shutdown. Rather than trying to follow traces etc. I went ahead and replaced the PWM & FET. Guess i'll try to trace the inputs more closely.
Did your TV die all of a sudden or slowly? Mine started slowly over time.
I am also fighting a continous blinking green light and have replaced the various caps with no success. I did also find no 5V or 3.3V on the power board. I powered up the power board by itself on the bench and found it comes up fine if I apply +5V to the PON2 input which appears to enable the 3.3V as as well as the 5V. I think the block diagram is not complete and doesn't show that the 3.3V is enabled by something else. I have been going through the other boards one-by-one checking to see what I can of internal power supply operation and all look good so far. Going further for me may be a lost cause without schematics. It looks to me that sometghing is unhappy and does not enable the PON2 line to power up the +5V and 3.3V.
- Kerry in San Diego
Kerry B. said:
I am also fighting a continous blinking green light and have replaced the various caps with no success. I did also find no 5V or 3.3V on the power board. I powered up the power board by itself on the bench and found it comes up fine if I apply +5V to the PON2 input which appears to enable the 3.3V as as well as the 5V. I think the block diagram is not complete and doesn't show that the 3.3V is enabled by something else. I have been going through the other boards one-by-one checking to see what I can of internal power supply operation and all look good so far. Going further for me may be a lost cause without schematics. It looks to me that sometghing is unhappy and does not enable the PON2 line to power up the +5V and 3.3V.
- Kerry in San Diego
I agree that something is making PON-2 unhappy. PON-2 turns on all the power throughout the TV. So when you supplied the voltages manually, did the TV turn on and everything look okay, or did you just try it to see if the other voltages power up on the POWER board?
My coworker said that the 3.3V going down PA connector is probably the voltages for the microprocessor. Without that, nothing will turn on. Hmm.. I was looking at the PA connector.. it's suppose to be getting 3.3V going to the DMD/Engine. Do you notice that there's 5V line also on the PA connector.. it never said that the 5V was going from the PWB-POWER board to the ENGINE. Maybe it's suppose to be from the ENGINE board to the PWB-POWER board which would explain why we don't have the 5V to power up all the other circuitry!! Well just a thought.
It's killing us without schematics.
gslacker: Mine was died slowly too. :( Since I had a plasma display in the family room I had this TV on the side. Always had strange problems with it. ie the fan would be always running even though the TV was off for days.
Shoot.. scratch that 5V line going to the PWB-POWER. just looked at the schematic and the 5V is being powered by the regulator. Have to trace the PON-2 to see what's driving that..
Hey Kerry, Where on the board is the PON-2 that you supply voltage to. I was trying to track it down on the board, but haven't found it yet. Supposedly the Q9A71, Q9A08, Q9A09, and IC9A11 are all connected to it, but don't seen any connection between all of them..
Ryo_Ohki2 said: Shoot.. scratch that 5V line going to the PWB-POWER. just looked at the schematic and the 5V is being powered by the regulator. Have to trace the PON-2 to see what's driving that..
PON2 signal comes from the signal board. On the power supply it is at K3 pin 4. No telling what kind of logic drives it, the signal board gets all kinds of status and power good signals. Getting to the signal board is also a major pain the you know what!
Mine also died slowly, would recover from the blinking LED with a power cycle at first, one cycle become two, then more, then totally dead!
I only fired up the power board by itself on the bench and applied the PON2 signal. I have not done this connected in the set as I'm a bit nervous about what damage might be done if the light engine & such tries to come up and some signals are bad or missing.
- Kerry in San Diego
Well I see PON-2 now.. duh.. on the interconnect schematic. :)
Okay now this makes more sense. If the POWER board gives 3.3V to the ENGINE board, the engine board supply the 5V to the SIGNAL board, then the SIGNAL board send the signal back to the POWER board.
To me this all points to the 3.3V on the POWER board.. well this is what I'm thinking.
I would be nervous to force 3.3V down the line to the ENGINE board to see if it would work..
FYI:
I traced it out and it seems that the PON-2 goes through a few transistors & resistors to get to each of the transistors shown on the block diagram.
I also figured out the transistor with Z markings. Pin 3 is the loan pin which is the out, and the (with the pin 3 facing upwards) the left pin is the input, and right pin the ground. Since I can't remember what BJT goes to what, it's easier to explain it as input and output. :)
Well I'm back to tracing that "SS/SD" path of the PWM controller chip. I believe that will lead me to my problem.. I hope.
Ryo_Ohki2 said: FYI: I traced it out and it seems that the PON-2 goes through a few transistors & resistors to get to each of the transistors shown on the block diagram. I also figured out the transistor with Z markings. Pin 3 is the loan pin which is the out, and the (with the pin 3 facing upwards) the left pin is the input, and right pin the ground. Since I can't remember what BJT goes to what, it's easier to explain it as input and output. :) Well I'm back to tracing that "SS/SD" path of the PWM controller chip. I believe that will lead me to my problem.. I hope.
Good info and good luck tracing the SS/SD pin. I'm thinking this is a good place to look.
According to the block diagrams the 3.3V from the PWM/FET is standby power, which I take to mean it should always be present. The PON2 signal seems to control the switched supplies, which would only come up when the power button is pressed.
Without schematics this is a real pain trying to figure out what controls what!
I applied +5V to the K3 connector pin 4 on the power board to supply the PON2 signal. On my power supply, that brought up the 5V as well as the 3,3V on the bench . I also initially thought that the 3.3 supply was a standby supply always on based on the crude block diagram but now don't believe that's true. I thinlk it would have been marked as 3.3VS if it was indeed alwasys on.
I think my next approach might be to try probing some of the signals at the Signal board connectors to see if I can identify any status signals that look bad comming from other boards. This will be just educated guesses since so little info is available.
- Kerry -
Kerry B. said:
I applied +5V to the K3 connector pin 4 on the power board to supply the PON2 signal. On my power supply, that brought up the 5V as well as the 3,3V on the bench . I also initially thought that the 3.3 supply was a standby supply always on based on the crude block diagram but now don't believe that's true. I thinlk it would have been marked as 3.3VS if it was indeed alwasys on.
I think my next approach might be to try probing some of the signals at the Signal board connectors to see if I can identify any status signals that look bad comming from other boards. This will be just educated guesses since so little info is available.
- Kerry -
Excellent call.. your right when I supplied 4.5V (didn't know if it was going to be 5V or 3.3V) it turned on the 3.3V line.. hence it's not a standby voltage..
I was really hoping it would be just the power supply, but looks like your right about checking out the Signal board since it supplys the PON-2 power. Wow.. this is starting to get more difficult by the minute. Wish I had a friend with a repair shop so I can just swap out boards to figure out which one is bad.
Hey Kerry & gslacker,
Have ever tried pulling the error code out of the TV? Page 23 on the service manual? I can't seem to get mine to give out a code.
Reason for asking is that my coworker told me that since it turns on, the next step is to see why PON-2 doesn't turn on. He told me typically it's due to the Status Monitoring circuitry. Try checking that out, IC7A00. Each item will give a signal to the IC to dictate a error. Possibly one of these items is prevening the IC from allowing PON-2 to turn on. He also told me to check the voltages across the speakers.. if speakers have voltage, then that can cause a fault. Note that the signal being sent to the IC7A00 might be quick signal.. Another FYI, the word SHORT means there's too much current draw detected on the power supply.
Well I hope we have the same problem and one of us figures it out.
I also have not been able to get an error code. I don't believe enough of the system is working to do that. I did just purchase the technical training manual which has very little additional usefull info for our problem. They say to replace the chassis if the power light blinks continously. They do however give a chart of voltages during bootup and it does show the 3.3V as off so this confirms what we have found out the hard way. There is really no other new info as the block diagrams & such are the same. I do plan to try looking at the status signals to see if they help.
I have model WS-55813. I also have the blinking reset light and have tried everything. Can somebody send me the instructions on how to fix this problem so i can get my TV working again. Thanks in advance!!!! [email protected]
Just a update.. I checked all my signal for the Status Monitoring Circuitry and found all was fine.
Kerry,
I then probed around the signal board and found 2 pins that had voltages I didn't expect. Connector J2 pin 3 & 9 should have 5VS, but only saw 0.8372V. Don't know if it was due to being in standby mode or it's bad.. Since we thought VS was for standby voltages.. then this could be consider bad. In truth I don't know if VS is to be consider standby voltages since +15V/-15V were on in standby but didn't have the VS next to it on the block diagram.
ALso I probed all the red voltages and they were there except for the 5VS I mention above.
Testing is becoming a pain. Have to make sure all grounds are connected to chassis, all cable are tie wrap short, etc.
Well, I guess its 3 for 3. If I force PON2 to 3.3V, I get 5V and 3.3V on the test points. Blinking LED does not go away. Need to find what is forcing PON2 to be low.
I agree, i'm not sure if 5VS is standby and should be on all the time or not. The block diagram does not show a 5VS on the power supply. Only other place I see 5VS is on the light engine and a pre-amp. The pre-amp looks like it relates to the remotes IR sensor and probably not the issue.
I'm going to try and look into the light engine a little more.
I looked at the DMD with PON2 forced on. J9 has all of the correct voltages. J14 looks good except for pins 11 and 12. Pin 11 is eng-powergood and is about 100mV. Pin 12 is engrst and 0V. The question now is, are these inputs or outputs? I'm going to make the assumption they are inputs for the moment and taht something else is forcing the DMD into reset.
Going to look at the signal board more and try to determine what some if its status signals are doing. Connector DC looks like a good starting point!
I found some adittional info on the web for helping to determine which board is at fault.
Try removing the USB connector on the chassis and power up. If the blinking stops after 70 secs, then the reader is bad.
Try disconnecting the FC connector to the FMT board and power up. If the blinking stops after 70 secs, then suspect the FMT card.
If the light still blinks, suspect the DM card.
In my case the blinkin stops after 70 secs when I pulled the FC connector on the FMT board. I can press the power button now and it turns green but of course nothing else happens. For fun I did check the power supply with the power light on but the switched supplies are still off. Well, now to look further at the FMT signals I guess.
- Kerry
Thanks for the suggestion. I'm looking at the 3.3V on the standby power supply. Looks like it's missing, but the IC's have the 12V.
Well you can send the documents to:
XXXX@XXXX
Thanks
The reason many of us are trying to do the repair ourselves is that we have tried taking the set to certified techs and find out the repair is too expensive... My estimate was over 1K and the certified tech would not guarantee his work (too many known problems with the set). So after dragging the non-functional set home I had a choice, chop it up and throw it in the trash can or try to fix it myself. If my repair causes "major board damage" the end result is the same - $3500 into the garbage can...
Ryo_Ohki2,
I seem to be having a similar problem. I've replaced caps on the DM, FMT, and signal boards with no luck. On the power supply I do not measure 5V or 3.3V at the test points in the upper right corner. I have replaced the PWM Controller (IC9A21) and FET (Q9A20) with no luck.
Interesting comment from Larry about the light engine loading it. Will have to look into that.
Larry do you have schematics for this beast?
sorry but they(mitsubishi), does not supply that a it is concidered not feild serivceable, tri state module can rebuild them or may have an exchange for it.
Thanks for your feedback, although I do agree with you about the difficuilty in epairing this line of tv set, I have had several NO, MANY folks who have repaired their DLP BY the info I have sullplied them but many who are unsucsesful Too!I myself have found many of these problem to be bad light engines along with a(part of the light engine called the DMD is the culprit). Again thanks for your input and feedack here at techlore.com just a note Mitsubishi dos not supply any service info on the light engine so. NO I cannot help all those who have asked for the schemtics or info on the DMD Board.
Oh man.. I don't know if your situation is the same with me, but with the POWER board not connected to anything, and not supply the voltage required for the DMD tells me it's definitely a issue in the POWER Board. After changing the PWM & FET, did you get that 3.3V coming out of the board? If so then it might be the DMD/Engine.
Larry, Where is the DMD board located? I'm not at home to look at my chassiss. Is it part of the whole module, or is it located somewhere else. If it's somewhere else, then I want to take a look at the DMD board to see if there's anything I reverse engineer and fix, assuming my POWER board fix is successful and the TV still doesn't work.
THanks
Okay.. Just tried turning on the POWER board to do some probing..
I heard this rapid clicking sound... Relay? I can't seem to reproduce it by cycling the power. Nuts.
No change after replacing the PWM and FET, still no 3.3V in that area of the supply. I do have 3.3V in other areas, but not at the test points or connector PA. (I think its PA, I'm not home and can't look at it now to verify!)
The PA connector supplies power to the light engine according the diagram I have. Will look into the DMD/light engine this weekend.
What other areas did you get the 3.3V? Your right about the 3.3V going to PA connector. If the block diagram is correct, then 3.3V is suppose to be a standby voltage that should be going down the PA connector on pins 6 & 8. Maybe the DMD is working but not getting the voltages to it. Well at least that is my current thinking. Going to consult with one of my coworkers that does do TV repair as a side job.
I just talked with my coworker. He looked at the schematic off the datasheet for the IRU3037 and based on my voltage measurements, he's determine that this PWM controller is in shutdown mode. He is not sure if it's forced to shutdown mode by a different part of the circuit or if the IC is defective. This guy is sharp as nails.. 40years in design engineering, and 40+ years in repairing stuff.
I would have to look at the board to give you exact locations, but there are some resistors in an area below and to the left of the PWM and FET, kind of the top left corner of the AC input stuff.
I agree the PWM could be in shutdown. One thing I've noticed on mine is pin 8 is ~0V. If its being used as a soft start feature in the design it should ramp up to a voltage at turn on. It could also be driven low by another circuit forcing it into shutdown. Rather than trying to follow traces etc. I went ahead and replaced the PWM & FET. Guess i'll try to trace the inputs more closely.
Did your TV die all of a sudden or slowly? Mine started slowly over time.
I am also fighting a continous blinking green light and have replaced the various caps with no success. I did also find no 5V or 3.3V on the power board. I powered up the power board by itself on the bench and found it comes up fine if I apply +5V to the PON2 input which appears to enable the 3.3V as as well as the 5V. I think the block diagram is not complete and doesn't show that the 3.3V is enabled by something else. I have been going through the other boards one-by-one checking to see what I can of internal power supply operation and all look good so far. Going further for me may be a lost cause without schematics. It looks to me that sometghing is unhappy and does not enable the PON2 line to power up the +5V and 3.3V.
- Kerry in San Diego
I agree that something is making PON-2 unhappy. PON-2 turns on all the power throughout the TV. So when you supplied the voltages manually, did the TV turn on and everything look okay, or did you just try it to see if the other voltages power up on the POWER board?
My coworker said that the 3.3V going down PA connector is probably the voltages for the microprocessor. Without that, nothing will turn on. Hmm.. I was looking at the PA connector.. it's suppose to be getting 3.3V going to the DMD/Engine. Do you notice that there's 5V line also on the PA connector.. it never said that the 5V was going from the PWB-POWER board to the ENGINE. Maybe it's suppose to be from the ENGINE board to the PWB-POWER board which would explain why we don't have the 5V to power up all the other circuitry!! Well just a thought.
It's killing us without schematics.
gslacker: Mine was died slowly too. :( Since I had a plasma display in the family room I had this TV on the side. Always had strange problems with it. ie the fan would be always running even though the TV was off for days.
Shoot.. scratch that 5V line going to the PWB-POWER. just looked at the schematic and the 5V is being powered by the regulator. Have to trace the PON-2 to see what's driving that..
Hey Kerry, Where on the board is the PON-2 that you supply voltage to. I was trying to track it down on the board, but haven't found it yet. Supposedly the Q9A71, Q9A08, Q9A09, and IC9A11 are all connected to it, but don't seen any connection between all of them..
PON2 signal comes from the signal board. On the power supply it is at K3 pin 4. No telling what kind of logic drives it, the signal board gets all kinds of status and power good signals. Getting to the signal board is also a major pain the you know what!
Mine also died slowly, would recover from the blinking LED with a power cycle at first, one cycle become two, then more, then totally dead!
I only fired up the power board by itself on the bench and applied the PON2 signal. I have not done this connected in the set as I'm a bit nervous about what damage might be done if the light engine & such tries to come up and some signals are bad or missing.
- Kerry in San Diego
I know the feeling about being nervous.
Well I see PON-2 now.. duh.. on the interconnect schematic. :)
Okay now this makes more sense. If the POWER board gives 3.3V to the ENGINE board, the engine board supply the 5V to the SIGNAL board, then the SIGNAL board send the signal back to the POWER board.
To me this all points to the 3.3V on the POWER board.. well this is what I'm thinking.
I would be nervous to force 3.3V down the line to the ENGINE board to see if it would work..
FYI:
I traced it out and it seems that the PON-2 goes through a few transistors & resistors to get to each of the transistors shown on the block diagram.
I also figured out the transistor with Z markings. Pin 3 is the loan pin which is the out, and the (with the pin 3 facing upwards) the left pin is the input, and right pin the ground. Since I can't remember what BJT goes to what, it's easier to explain it as input and output. :)
Well I'm back to tracing that "SS/SD" path of the PWM controller chip. I believe that will lead me to my problem.. I hope.
Good info and good luck tracing the SS/SD pin. I'm thinking this is a good place to look.
According to the block diagrams the 3.3V from the PWM/FET is standby power, which I take to mean it should always be present. The PON2 signal seems to control the switched supplies, which would only come up when the power button is pressed.
Without schematics this is a real pain trying to figure out what controls what!
I applied +5V to the K3 connector pin 4 on the power board to supply the PON2 signal. On my power supply, that brought up the 5V as well as the 3,3V on the bench . I also initially thought that the 3.3 supply was a standby supply always on based on the crude block diagram but now don't believe that's true. I thinlk it would have been marked as 3.3VS if it was indeed alwasys on.
I think my next approach might be to try probing some of the signals at the Signal board connectors to see if I can identify any status signals that look bad comming from other boards. This will be just educated guesses since so little info is available.
- Kerry -
Excellent call.. your right when I supplied 4.5V (didn't know if it was going to be 5V or 3.3V) it turned on the 3.3V line.. hence it's not a standby voltage..
I was really hoping it would be just the power supply, but looks like your right about checking out the Signal board since it supplys the PON-2 power. Wow.. this is starting to get more difficult by the minute. Wish I had a friend with a repair shop so I can just swap out boards to figure out which one is bad.
Hey Kerry & gslacker,
Have ever tried pulling the error code out of the TV? Page 23 on the service manual? I can't seem to get mine to give out a code.
Reason for asking is that my coworker told me that since it turns on, the next step is to see why PON-2 doesn't turn on. He told me typically it's due to the Status Monitoring circuitry. Try checking that out, IC7A00. Each item will give a signal to the IC to dictate a error. Possibly one of these items is prevening the IC from allowing PON-2 to turn on. He also told me to check the voltages across the speakers.. if speakers have voltage, then that can cause a fault. Note that the signal being sent to the IC7A00 might be quick signal.. Another FYI, the word SHORT means there's too much current draw detected on the power supply.
Well I hope we have the same problem and one of us figures it out.
I also have not been able to get an error code. I don't believe enough of the system is working to do that. I did just purchase the technical training manual which has very little additional usefull info for our problem. They say to replace the chassis if the power light blinks continously. They do however give a chart of voltages during bootup and it does show the 3.3V as off so this confirms what we have found out the hard way. There is really no other new info as the block diagrams & such are the same. I do plan to try looking at the status signals to see if they help.
I have model WS-55813. I also have the blinking reset light and have tried everything. Can somebody send me the instructions on how to fix this problem so i can get my TV working again. Thanks in advance!!!! [email protected]
Don't know, but I suspect it's around $150 to $300.
I believe I heard that it's backordered..
Just a update.. I checked all my signal for the Status Monitoring Circuitry and found all was fine.
Kerry,
I then probed around the signal board and found 2 pins that had voltages I didn't expect. Connector J2 pin 3 & 9 should have 5VS, but only saw 0.8372V. Don't know if it was due to being in standby mode or it's bad.. Since we thought VS was for standby voltages.. then this could be consider bad. In truth I don't know if VS is to be consider standby voltages since +15V/-15V were on in standby but didn't have the VS next to it on the block diagram.
ALso I probed all the red voltages and they were there except for the 5VS I mention above.
Testing is becoming a pain. Have to make sure all grounds are connected to chassis, all cable are tie wrap short, etc.
Well, I guess its 3 for 3. If I force PON2 to 3.3V, I get 5V and 3.3V on the test points. Blinking LED does not go away. Need to find what is forcing PON2 to be low.
I agree, i'm not sure if 5VS is standby and should be on all the time or not. The block diagram does not show a 5VS on the power supply. Only other place I see 5VS is on the light engine and a pre-amp. The pre-amp looks like it relates to the remotes IR sensor and probably not the issue.
I'm going to try and look into the light engine a little more.
I looked at the DMD with PON2 forced on. J9 has all of the correct voltages. J14 looks good except for pins 11 and 12. Pin 11 is eng-powergood and is about 100mV. Pin 12 is engrst and 0V. The question now is, are these inputs or outputs? I'm going to make the assumption they are inputs for the moment and taht something else is forcing the DMD into reset.
Going to look at the signal board more and try to determine what some if its status signals are doing. Connector DC looks like a good starting point!
Damn, wish I had schematics!!!
I found some adittional info on the web for helping to determine which board is at fault.
Try removing the USB connector on the chassis and power up. If the blinking stops after 70 secs, then the reader is bad.
Try disconnecting the FC connector to the FMT board and power up. If the blinking stops after 70 secs, then suspect the FMT card.
If the light still blinks, suspect the DM card.
In my case the blinkin stops after 70 secs when I pulled the FC connector on the FMT board. I can press the power button now and it turns green but of course nothing else happens. For fun I did check the power supply with the power light on but the switched supplies are still off. Well, now to look further at the FMT signals I guess.
- Kerry
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