Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

[Larry420r]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

all the points on the heat sinks read 002

[Larry420r]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

the 12 points. ( 4 on each sink )
on all heatsinks are reading 002 ( when I touch meter to left and right side)

[dick_barton]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

You really need to remove them carefully and see if the short circuit has gone.

[Larry420r]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

You really need to remove them carefully and see if the short circuit has gone.

I just finished supper now its reading 001


so I just unscrew the screw on the mosfets and remove just the heatsink?

[dick_barton]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

I cannot really tell you because I cannot see how they are fitted to the heatsink.
Normally you can remove them without removing the heatsink. Keep a note of which one was soldered in where. For example Q601 Part No. FP2345, Q603 Part No.AF1123

[Larry420r]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

oh I just clued in.... you meant check the readings on the mosfets.

one sec, I will do that right now

[dick_barton]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

I've just noticed that you've posted picture. Missed them because it was on the previous page.
Check across the pins of each device in diode mode and if the reading is low then you need to unsolder it and remove it. Then check the next device and repeat until you find all the shorted devices.

[Larry420r]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

right side heatsink ( singular )

Going from top to bottom, 4 in total on this heatsink

Top - 364 part -30g124
next down - 364 part - auk71514
next - 368 - part 30g124
last - 368 - part auk71514

left top heatsink 4 aswell
top- 001 part auk 71514
next -001 part rjp30h1
next- 864 part auk61317
next- 864 part auk61317

left bottom heatsink 2 mosfets on it

top - 001 part rjp30h1
bottom - 001 part auk71513

[dick_barton]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

right side heatsink ( singular )

Going from top to bottom, 4 in total on this heatsink

Top - 364 part -30g124
next down - 364 part - auk71514
next - 368 - part 30g124
last - 368 - part auk71514

left top heatsink 4 aswell
top- 001 part auk 71514
next -001 part rjp30h1
next- 864 part auk61317
next- 864 part auk61317

left bottom heatsink 2 mosfets on it

top - 001 part rjp30h1
bottom - 001 part auk71513

The ones the read 001 need to be taken out and checked out of circuit.

[Larry420r]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

the two on the left bottom heat sink are going to be next to impossible to remove without removing everything cause there is caps in the way

[Larry420r]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

removing the caps then gonna pull the mosfets.

[dick_barton]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

I have a small right-angled ratchet screwdriver for getting into limited spaces.

[Larry420r]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

k just finished getting all 4 out and the caps out.

testing right now

[Larry420r]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

left top heatsink 4 aswell
top- 001 part auk 71514 -- new reading 370
next -001 part rjp30h1 -- new reading - 002
next- 864 part auk61317
next- 864 part auk61317

left bottom heatsink 2 mosfets on it

top - 001 part rjp30h1new read - 002
bottom - 001 part auk71513 - new read 362

[dick_barton]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

left top heatsink 4 aswell
top- 001 part auk 71514 -- new reading 370
next -001 part rjp30h1 -- new reading - 002
next- 864 part auk61317
next- 864 part auk61317

left bottom heatsink 2 mosfets on it

top - 001 part rjp30h1new read - 002
bottom - 001 part auk71513 - new read 362

Are those readings taken of the components after they have been removed from the circuit board.

Any of the devices which still measure 001/002 out of circuit are faulty.

If you measure VS to ground with your meter set to 200 ohms, has the low resistance you gave earlier now gone?

It's late here so I'm off for the night.

[Larry420r]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

not getting anything now on the meter.

[Sevenqi]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

Normally the following MOSFETs were damaged, replace them all, you need to remove the nearby caps before remove them.
1. Remove related caps (c4702,c4703, green color) so you can remove RJP30H1.
2. Remove the following MOSFETs (Most likely they all shorted)
Q4202 (30G124)
Q4503(30G124)
Q4101(30G124)
Q4104(30G124)
Q4301(RJP30H1)
Q4302(RJP30H1)
3. Measure if still any short, if yes, please check the following diodes:
D4202(SF10A00H)
D4505(SF10A00H)
D4103(SF10A00H)
if they were shorted, replace them with good ones.
4. Replace the 30G124 and RJP30H1 with good ones.
5. Now there shouldn't have any short, install the x-main to the TV.

[dick_barton]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

I'm not familiar with this set but if the Xmain, which we know is damaged, is connected across to the Ymain, then I would check that there are no short circuit components on the Ymain board before refitting the repaired Xmain.

I would also take Sevenqi's advice and change all the Mosfets and diodes he listed.

[CapLeaker]

Re: Here I Sit, Losing my mind. Haha. Samsung Pn51d550c1fxza

Here is my run in with the X-Main, if that's any help:
https://www.badcaps.net/forum/showthread.php?t=57039