Goodmans GML22W29HDVF / Vestel 17mb29 main board

[mrfriss]

Just to be sure, I quickly made the attached image to check for the possible repair options for adding/replacing a capacitor.

Could someone quickly check if I am looking at the right components and connections?

Option #1 replaces the current 470uF capacitor for a 1000uF, I think I'm looking at the correct part (C141)
Option #2 adds a 1000uF capacitor, but I'm not sure I'm connecting this in the right way... Is that cube part L107 and is the output on the right?

Thank you!

[Contrast John]

Hi Again
Option #2 is the one I used. Exactly as in your picture. Soldered the positive of the capacitor to the right hand tag of L107 (output) and attached the negative leg of the capacitor to the earth screw.
Good Luck
John.

[mrfriss]

An update again from my side; I tried adding and changing capacitors, but no luck...

I found this thread: http://www.tv.quuq.org/forum/index.php?topic=3433.0
It is somewhat the same topic as in here, but the problem has been found in the psu.
I will try adding a 1k resistor between pin 1 of IC301 and ground tomorrow.

While fiddling with capacitors I did some measurements and found that when the set is plugged in and the power button is on, the standby pin puts out around 1,6V. The documentation says standby is ON between 2 and 5 volts and off when 0. Would it be an option to ground this pin so it stays 0?

Another thing is that my unit seems to be stuck in some kind of test mode; when I plug it in, wait for it to power on (blue led comes on) and press the program+ or program- button, it shuts off the blue led, but after 10 seconds or so it starts up the display, flashing the screen slowly and showing black to white gradients...

Finally I found the ebay seller who offers replacement sets, I emailed him, but he want to have my defect board. Clearly he knows how to overcome the problem, but won't share it.
While looking at his pictures though, I noticed a different capacitor on his boards; he seems to have changed c536, maybe someone else knows if this could be an option that makes sense.

Thanks!

[Contrast John]

Hi mrfriss
The 1k resistor mod is a possible cure for a lazy ccfl backlight tube. If this was your problem you would have the symptom of sound ok but no backlight illumination. Switching the set in and out of standby would not be an issue.
Seem to recall that the documentation about the standby switching voltage was incorrect in some way but can't remember the exact details.
Think your set is exhibiting a fault different to mine because it appears that you are able to bring it out of standby. From the description it sounds like a corrupted eeprom IC stuck in some sort of test mode. Try holding the menu button on the remote control for a few seconds while the screen is flashing. Sometimes it can act as a reset.
Checked on the circuit for c536. Assuming the numbers are the same on this version c536 also decouples the standby 3.3 volt line - just a bit further downstream. So upgrading it would have the same effect as either of the capacitor mods you have tried.
Regards
John.

[mrfriss]

Unfortunately no luck with the menu button on the remote or set itself...

But you are right, I CAN get out of standby mode, either with the buttons on the set itself or remote control. Only thing is that it goes into some kind of testing mode.
I'm going to look into the eeprom, maybe there is an alternative way to get it out of reset or something.

If anyone has any thoughts, please let me know!

[mrfriss]

Another thought... could someone guide me through the menu structure to reset the chip?
I believe my set is fully working, but stuck in a test display sequence.

So after pressing 'menu', '4', '7', '2', '5', how many ups, downs, left rights do I need to do a "INIT NVM"?

What other options do I have in this service menu?

Thanks!

[Contrast John]

Hi mrfriss
From memory- MENU 4725 should bring up the service display. Scroll down to RESET option. Press right scroll button. You should see another screen that tells you to press the green button. Press green and it should reset the software before switching itself to standby.
Best of Luck
John.

[mrfriss]

Thank you, but not exactly what I meant...

I need exact button presses to reset the device (or do something else that could get my device out of display test mode).

So if anyone has a device with this main board, please enter the service menu and post the options or take a picture and share it, somewhat like this (including sub menu's): http://www.djsmiley.com/got/pics/techwoodtv/hires/dscf9824.jpg

Frustrating that the set fully works, except displaying the images (sound works and it responds to button presses)

[romanko]

HI again guys. I didn`t have enough time to have look back on these sets but fault is definitely on the PSU board,that`s my opinion. Like I set before, I tried change couple working chips but without change.Few months ago I change all those Big caps,for value at least half more  like they was.One of these sets is working over good few months with no problem at all and customer is fully satisf. Guys, do not put tv into the INIT NVM reset mode .That is only wasting the time.I did this on other two sets before and then I has to reprogram all settings in Service mode.Every f...... step.reset of all factory settings so this is a bad idea for me.My Set is coming on after about 10 seconds when blue light is off,self test or something like that,no idea but then working perfectly. I`ll have the same unit for repair on table this saturday.Caps should have a Value of around 1200 uF per 1 Amp floating current DC.These G-Luxon,Teapo and similar family of 85 °C chineese  piece of shity caps are not suitable for switching power supply. Use real low ESR 105°C selected brands of caps and also check the datasheet.Main board rechecked for bad caps and dry joints by ESR and other eguipment.1000uF replaced by 1500 and other with higher value. Do not exceed too much,double value my cause some fault.Try this ,works for me .Good luck.