Samsung LE40M86BD Not Caps/Flash?

[CraXyOW3]

Hi, first time posting here so bare with me!

Yes, i have first searched the forums and checked and double checked everything.
Have found most of my answers here just by reading! Now i have to post.

So i got this Samsung LE40M86BD, it was repaired once by me with the typical "bad caps" procedure about 1½ year ago. Now it did the same again, clicking and won't turn on.

I checked the caps but there are no apparent or otherwise visible bulges or other defects, anyway, swapped them just in case. Still clicking.

Read up on these forums and saw the eeprom error, i added a tactile switch for lazy shorts, feels better for me than just 2 bare wires.
Even this procedure didn't work BUT, when reseting eeprom the tv sets it selves in standby instead of just turning on, so my tought is, mainboard should be working ok?

Anyway, one thing that is noticable is the TM801S Transformer is "whizzing", not the typical high pitch noise, also this "whizzing" is increased as the relay kicks in and goes away the moment the relay goes off.

What i can tell if i still can read schematics the DM851 should read 12/13volts and DM857 should give off 5 volts?
I have typed down the value i get on respective components on the following image.
Also in yellow the changed caps (again.)

PSU number bn44-00165A.



EDIT:
Reference thread before this question was asked -> Samsung LE40R88BD Clicking Relay

[marky mark]

Trying to blank the eeprom doesn't always work, you might of just screwed it up, so well done for being lazy. Have you looked for dry joints on the transformer?

[CraXyOW3]

No dry joints,was one of the first thing i was looking for but one can never be sure as they can have micro fractures.
I did put fresh solder on it just in case, but no dice :/

[jordan]

ICS-802 (TL-431) ???

[CraXyOW3]

Found only 2 matching components to TL-431, Named UM851 & UB851 with designation KIA431A.
In the schematics it's labeled KA431 and UM851 is in association with the TM801S with the noise so i am going to measure the values of those two Shunt Regulators and thanks for such a precise answer!

[jordan]

bn44-00165A.

[CraXyOW3]

The shunt regulators showed good values and no shorts, altho i diode checked the optocouplers in the vicinity and PC802S is showing double the value as the other two PC801S, PC803S, might that optocoupler be defective then?

[dynomo]

The shunt regulators showed good values and no shorts, altho i diode checked the optocouplers in the vicinity and PC802S is showing double the value as the other two PC801S, PC803S, might that optocoupler be defective then?

Just pulled a psu out my parts bin. PC802s is reading higher on this board in situ if that helps. Check fuse FW802. Had one once where this fuse had blown along with IC UB801S and diode ZB802.

Other pain in the ass faults I have had with these PSU's is the variable resistor VR801 going bad causing the 2 fets M1801S and M1802S to go short circuit. But that normally duffs the backlight inverter only on the PSU.

I would lean towards the eeprom myself on your set.

[CraXyOW3]

FM802 fuse checks out ok, same with FM801, diode ZB802 passes the diode test tho i get .04 v when powerd.
VR801 is measuring 16k and i got no shorts on MI801S/MI802S

DB801 is a bit dubious for me, i get the ok with the diode test with my dmm, but when measuring the voltage it only spikes, i can't read it.

The transformer noise is still there too, could it be plausible for the transformer to make that "whizzing" noise due to the memory flash?


EDIT:
Have orderd the flash memory. But still, what is it with the transformer?

[Keith]

Hi,

You need to force the power supply on to test if it is working.

Keith

[CraXyOW3]

I do this by shorting PS ON?

[CraXyOW3]

Recieved the flash, replaced it and now the TV is alive, BUT i am greeted with some kind of inverted colors.

Could this be a setting in the "bios" sort of? Also there is a wierd buzzing sound from the speakers and each 10Sec or so they give of a short bass sound.

[Keith]

Check screen settings and main board selection, if active, in service mode.

Sometimes there are different flash data for different screens, so you may have fitted the wrong flash!

When you say you changed the flash, have you changed the I2C eeprom or SPI eeprom?

Keith

[t1412]

i'd check lvds settings in the service mode

regards
shaun

[CraXyOW3]

I have checked the settings in the service menu and changed boardtype that more or less resembles the brands and such that is on the mainboard.

Finally i got a good picture but from time to time it seems to revert to the previous state in picture.
Tho with a restart it is gone once again. Also before the problem occurs momentarily again the screen starts to flicker, but not the usual cathode flickering but just simply a screen flicker.

One second note too, the sound from the speakers is the same as before.