Samsung PN64E550D1FNZA

[etechb]

I have been working on this unit for about two days. I believe the set was struck by lightning but can't confirm.

I have been concentrating on the PS board as I am getting some strange stuff going on. I am getting 120V into the board but cannot record anything at the Vs and Va test points. they are both either at or near zero at all times.

I have disconnected all of the other boards from the PS and tested the voltages again and still receive the same thing.

The Standby LED comes on and the blinks 5 times and then you can here the relay click to start over. It keeps doing this time and time again.

Has anyone seen this before and what else should I be looking for?

[budm]

Re: Samsung PN64E550D1FNZA

The standby power supply must be working otherwise you will not be getting any LED indicator.
You need to up load the pictures of the whole backside of the TV showing all the boards, then pictures of at least the power supply board.
The power supply board should have P/N with something like BNXX-XXXXXZ.
Vs power supply is switched on by the command signal from the main board, the main power supply section is also switched on when the PS-ON pin is grounded.

[etechb]

Re: Samsung PN64E550D1FNZA

Thank you Bud.

The main board is plugged in but I am not getting anything on Vs. I will ground the PS ON and recheck voltages. If I do this I should get the full voltage levels right?

[budm]

Re: Samsung PN64E550D1FNZA

You need to find out what the DCV on the PS-ON pin is when TV is OFF and when TV is switched ON. Do not try to GND anything until we know the status of the command signals first.
Once we know that we have the PS-ON command signal then we need to find out if we have PFC Boosted Voltage or not on the main filter cap, there are steps that need to follow first to narrow down the cause of the problem. Right now we cannot really tell until we see the good clear pictures of the boards and the model number of this power supply board.
Vs command signal has to be present for the Vs power supply to come on but it needs the Boosted Voltage to run.

[martino]

Re: Samsung PN64E550D1FNZA

ps-on needs to be pulled to ground and vs-on needs to be pulled up.
meaning:resistor of approx 560 ohm(give or take) from ps-on to ground.
same size resistor from vs-on to 5volt standby.

These psu's are notorious for blowing themselves up due to bad soldering on the fets.
I'd check the fet's and diodes on the heatsink for shorts.QP802, 804, QS802, 804

Shopjimmy does have a repair kit for these.
https://www.shopjimmy.com/samsung-bn...repair-kit.htm

If you do use the repair kit,do NOT replace UQ802. It is a blank chip that needs to be programmed,old one will be fine.


Sorry for the interruption Couldn't help myself,back to budm...(drops mic and carefully tip toes of stage......)

[etechb]

Re: Samsung PN64E550D1FNZA

PS board is bn44-00515a. I will take pictures tomorrow and post them.

[Andyy]

Re: Samsung PN64E550D1FNZA

Shopjimmy does have a repair kit for these.
https://www.shopjimmy.com/samsung-bn...repair-kit.htm

If you do use the repair kit,do NOT replace UQ802. It is a blank chip that needs to be programmed,old one will be fine.

Also shopjimmy's kit does NOT contain RS833 and RS819. These are 47Ω 0.125watt (0805 surface mount package) gate drive resistors for QS802 & QS804. I found both my gate drive resistors open circuit when I repaired my board. If you can't get 0805's you can squeeze 1206's onto the pads. DON'T use 0603's as their power rating 0.1watt maybe insufficient.

[etechb]

Re: Samsung PN64E550D1FNZA

I took these pictures in a rush and I will get better ones tonight.

[budm]

Re: Samsung PN64E550D1FNZA

BTW, you should check all those parts used in the SJ Kit on your board to see if they are OK.

SJ pictures as a ref to compare to your board:
Samsung BN44-00515A (P64FW_CPN) Power Supply Unit.
Pictures provided by shopjimmy.

[etechb]

Re: Samsung PN64E550D1FNZA

Bud,

I am pretty new at this. Can I test them in circuit for shorts with a multimeter?

[alfredomfr1]

Re: Samsung PN64E550D1FNZA

I need to know the value of RS835

[Keshenatech1]

Re: Samsung PN64E550D1FNZA

ps-on needs to be pulled to ground and vs-on needs to be pulled up.
meaning:resistor of approx 560 ohm(give or take) from ps-on to ground.
same size resistor from vs-on to 5volt standby.

These psu's are notorious for blowing themselves up due to bad soldering on the fets.
I'd check the fet's and diodes on the heatsink for shorts.QP802, 804, QS802, 804

Shopjimmy does have a repair kit for these.
https://www.shopjimmy.com/samsung-bn...repair-kit.htm

If you do use the repair kit,do NOT replace UQ802. It is a blank chip that needs to be programmed,old one will be fine.


Sorry for the interruption Couldn't help myself,back to budm...(drops mic and carefully tip toes of stage......)

I don't see a UQ802, do you mean US802? My kit only came with ICP801 and US801. There is a US802 on the board, but the kit did not come with that one. Maybe they've realized that and taken it out of the kit since this post was 1st made in 2016?
Anyway I bought the kit and rebuilt my power board. The TV turns on and off, logic seems to be working, but the screen won't light up and I noticed the VS starts up fairly close to specs but then keeps dropping as I leave it run. I was afraid to run it too long like that. How long does this model need to run before the screen lights up, should it be almost immediate? Also, how can I determine if I still have power board problems, or if the problem is elsewhere such as a Y sustain board and/or buffer?

[brendan2330]

Re: Samsung PN64E550D1FNZA

I don't see a UQ802, do you mean US802? My kit only came with ICP801 and US801. There is a US802 on the board, but the kit did not come with that one. Maybe they've realized that and taken it out of the kit since this post was 1st made in 2016?
Anyway I bought the kit and rebuilt my power board. The TV turns on and off, logic seems to be working, but the screen won't light up and I noticed the VS starts up fairly close to specs but then keeps dropping as I leave it run. I was afraid to run it too long like that. How long does this model need to run before the screen lights up, should it be almost immediate? Also, how can I determine if I still have power board problems, or if the problem is elsewhere such as a Y sustain board and/or buffer?

how did you go with the tv? im trying to learn a bit before attacking myn. the kit seems to be the way to go...