Samsung LN32A330J1D Problems

[gitano]

I have a Samsung LN32A330J1D, Model Code "xza". The power supply unit model is BN44-00191A. The Main Board (MB hereafter), has a sticker with the following number on it: BN97-02111F. However, the board is stenciled with:

Jade Board
BN41-00965A
2008.01.14

Here are pictures. First the MB's labeling:


Next, the PSU whole:


The TV will not power on but the red light in the on-chassis power button is on/lit when the unit it plugged in.

Here are the events I think are relevant that preceded the failure:
1) Power supply to the house fluctuated during a wind event. This could be called a power "surge" I suppose, but it wasn't really a "surge". It was repeated on/off cycling over the course of about 3 to 5 seconds. My house is FULL of other electronic equipment including computers and other TVs. No other device in the house was effected by this power-to-the-house issue.
2) It was at least 12 hours between the above power fluctuation event and when I attempted to use the TV.

I have spent the past four days searching the internet for ways to address the issue. Based on that search I 'opened it up' and checked the output of the PSU to the MB. Here is picture of the plug and voltage values for each pin:


You will note the annotation. That is the ONLY pin with ANY voltage. All others have 0.0 VDC readings. This appears to be a "switched power supply" to me. If so, it occurred to me that it might not provide readings without feedback from the MB.
1) Is that correct?
If not, it strongly suggests that the PSU is "fried".

Based on information obtained at this site, I attempted a "factory reset". No joy there.

I have carefully inspected both boards. There is no sign of damage: no bulged capacitors; no "burn" spots; no smell of 'cooked' components; no sign of the smoke being let out of any component.

I checked the voltage at three "TP" points. Here are pictures of those Test Points:


and


There was a consistent reading of 330 VAC at all of those points.

Any assistance "you" could provide would be greatly appreciated.

Paul

PS - For completeness, here's a picture of the MB:


Paul

[ReeceyBurger123]

Re: Samsung LN32A330J1D Problems

With the Mainboard unplugged does the backlight come when you apply power to the tv ?

[gitano]

Re: Samsung LN32A330J1D Problems

With the Mainboard unplugged does the backlight come when you apply power to the tv ?

If by "backlight" you mean the little red light in the on-chassis power button: "No".

Paul

[gitano]

Re: Samsung LN32A330J1D Problems

With regard to posting images:

I read here the following here: https://www.badcaps.net/forum/member.php?u=18381

Please do not post inline and offsite as they slow down the loading of pages.

I cannot tell if retiredcaps is referring to images in the above admonition. Most sites I use PREFER that users use an off-site image server and post a link to that image. If retiredcaps is in fact referring to images posted here, I assume the 'management' wants me load my images to their server.

Is that correct?

Paul

[ReeceyBurger123]

Re: Samsung LN32A330J1D Problems

If by "backlight" you mean the little red light in the on-chassis power button: "No".

Paul

No, re-reading this when you unplug the Mainboard you get no voltages ? Which would be indicating a Psu failure.

[gitano]

Re: Samsung LN32A330J1D Problems

... when you unplug the Mainboard you get no voltages ?

Correct.

Which would be indicating a Psu failure.

Thanks, that's what I thought.

Are any other diagnositics necessary?

Paul

[budm]

Re: Samsung LN32A330J1D Problems

No, re-reading this when you unplug the Mainboard you get no voltages ? Which would be indicating a Psu failure.

Unfortunately this power supply board BN44-00191 does not have pull-up resistors for the PS-ON (PWR-ON), or BL-ON pins, he will need resistors to do the force on.
What he should do at this point is to put the connector back in place, hit the power switch and report the DCV of each pin with pin numbers and pin names so we can see what is missing.
He only has STBY power supply at this point.

[gitano]

Re: Samsung LN32A330J1D Problems

We'll see what "he" can do.

By the way: "Hit the power switch" does nothing. Neither with the remote nor manually with the on-chassis power button.

Paul

[gitano]

Re: Samsung LN32A330J1D Problems

With the MB cable connected and line power available, all of the pins read the correct nominal values. Clearly a switched PS.

I assume this means that the PSU is functioning properly?

Paul

[budm]

Re: Samsung LN32A330J1D Problems

"With the MB cable connected and line power available, all of the pins read the correct nominal values" so you are getting correct Voltage value for the signal pins ON/OFF?
This pin 1 (ON/OFF) should be <1VDC when TV is OFF, and >2.5VDC when power switch is ACTIVATED.
Do you get the 24VDC on the 24V output pin?
BTW, when the >2.5VDC is present, you should have >380VDC between the tow legs of the main filter cap in the primary side if the PFC Voltage booster is working, and switched 24VDC on the CN803/803, and switched 12V and 13V.
Also see if you have >2.5VDC on pin 12 (BL-ON) of CN802/803.

[gitano]

Re: Samsung LN32A330J1D Problems

"No" to most of your questions.

Specifically:

so you are getting correct Voltage value for the signal pins ON/OFF?

There was no voltage specified. The value measured was 3.93VDC.

This pin 1 (ON/OFF) should be <1VDC when TV is OFF, and >2.5VDC when power switch is ACTIVATED.

I have no way to "activate" this switch other than to plug the ribbon cable in. With the cable connected between the PSU and the MB, the voltage value is 3.93VDC.

Do you get the 24VDC on the 24V output pin?

There are no pins designated with voltage values of 24.
Here is a picture of the plug and the nominal voltage values associated with each pin:

Pin 1 is on the left and toward the top of the picture. Pin 24 is on the right and toward the bottom of the picture. The numbering scheme is in the bottom of the PCB.

The measured voltages at every pin are the same as the nominal per the stenciling. Pin 1 did not have the values you gave, or any value specified.

BTW, when the >2.5VDC is present, you should have >380VDC between the tow legs of the main filter cap in the primary side if the PFC Voltage booster is working,

I assume you mean on Pin 1. If that assumption is correct, then I get 330 VDC, not 380.

Also see if you have >2.5VDC on pin 12 (BL-ON) of CN802/803.

Without going to the components, but rather staying at the plug, I have 0.0VDC on pin 12. However, the specified voltage for that pin is "gnd".

Here are the nominal values (see picture), for each pin with their corresponding measured values:

Pin# . . . . Nominal Voltage . . . . . . Measured Value (VDC)
1 . . . . . . . . ."On/Off" . . . . . . . . . . . . . 3.93
2. . . . . . . . . . "N/C" . . . . . . . . . . . . . . 0.0
3 . . . . . . . . . St-By . . . . . . . . . . . . . . 0.0
4 . . . . . . . . . gnd . . . . . .. . . . . .. . . . . 0.0
5 . . . . . . . . . gnd . . . . . .. . . . . .. . . . . 0.0
6 . . . . . . . . . gnd . . . . . .. . . . . .. . . . . 0.0
7 . . . . . . . . . 12v . . . . . . . . . . . . . . . . 12.0
8 . . . . . . . . . 12v . . . . . . . . . . . . . . . . 12.0
9 . . . . . . . . . gnd . . . . . .. . . . . .. . . . . 0.0
10 . . . . . . . . gnd . . . . . .. . . . . .. . . . . 0.0
11 . . . . . . . . gnd . . . . . .. . . . . .. . . . . 0.0
12 . . . . . . . . gnd . . . . . .. . . . . .. . . . . 0.0
13 . . . . . . . . 5.3v . . . . . . . . . . . . . . . . 5.28
14 . . . . . . . . 5.3v . . . . . . . . . . . . . . . . 5.28
15 . . . . . . . . 5.3v . . . . . . . . . . . . . . . . 5.28
16 . . . . . . . . 5.3v . . . . . . . . . . . . . . . . 5.28
17 . . . . . . . . gnd . . . . . .. . . . . .. . . . . 0.0
18 . . . . . . . . gnd . . . . . .. . . . . .. . . . . 0.0
19 . . . . . . . . 13v . . . . . . . . . . . . . . . . 12.78
20 . . . . . . . . gnd . . . . . .. . . . . .. . . . . 0.0
21 . . . . . . . . 13v . . . . . . . . . . . . . . . . 12.78
22 . . . . . . . . 13v . . . . . . . . . . . . . . . . 12.78
23 . . . . . . . . . "N/C" . . . . . . . . . . . . . . 0.0
24 . . . . . . . . . "N/C" . . . . . . . . . . . . . . 0.0

I appreciate your patience and assistance.

Paul

[budm]

Re: Samsung LN32A330J1D Problems

"There are no pins designated with voltage values of 24." If you look at your board you will see two more white connectors CNM802, and CNM803. Your TV only uses CNM802, pin 1~5 are 24V, PIN 6~10 are GND, pin 11~14 pin names do not quite match the diagram of the board so to find out of the main board is sending (when PS-ON is present on pin 1 of CNM801)the BL-ON, A/D (Analog Dimming), and P/D (PWM Dimming) signals or not you will need to check the CNM804
Pin 1 for BL-ON
Pin 2 for A/D
Pin 3 for P/D
"I assume you mean on Pin 1. If that assumption is correct, then I get 330 VDC, not 380" 330VDC is not normal.
So if you do have the 24VDC, BL-ON, A/D, P/D then you should have backlights.

'I have no way to "activate" this switch other than to plug the ribbon cable in. With the cable connected between the PSU and the MB, the voltage value is 3.93VDC.' You do have power switch (or you can use the Remote) on the TV to turn the TV on and off, so that Voltage on pin 1 should toggle between <1V (when you hit the power switch to turn the TV off, and > 2.5V (when you hit the power switch to turn the TV ON). If the Voltage on pin 1 is staying at 3.93V all the time when you hit the power switch ON and OFF then then main board has at least one stuck signal problem, but what we want to make sure is that your power supply and the inverter boards are OK or not that is why we need to find out if the main board is sending out BL-ON, A/D, P/D or not.
We want to find out how many boards are bad in your TV first that is why we are testing all the Voltage and the signals.

[gitano]

Re: Samsung LN32A330J1D Problems

I didn't note your CN802 and CN803. I am getting 24VDC on the correct pins. I am NOT getting 380 VDC anywhere on the board: 330VDC is the measurement.

I get the following values for pins 11 through 14 on CN803:
11 - "A/D" = 3.48VDC
12 - "B/L" = 0.11VDC
13 - "P/D" = 4.44VDC
14 - GND = 0.0

Pins 1 through 5 have 24 VDC, and pins 6 through 10 are ground.

Paul

[gitano]

Re: Samsung LN32A330J1D Problems

Just read your edit of post #12. There is a lot more clear now.

There is no response from the TV when using either the remote or the on-chassis power button. There is no change in the voltage on connector to the MB. Therefore, I assume that there is "at least one stuck signal problem".

I appreciate - from a philosophical and practical perspective - the step-wise walk through the troubleshooting. It is the 'right' (smart) way to troubleshoot. However, it's been a long time since I was up to my elbows in a piece of gear. While the principles are the same, the terminology is slightly different and the layout and nomenclature on PCBs has clearly evolved. (For example: "Test points" used to be sequentially numbered with no duplicates. This board has several with the same number.) Please bear with me, and assume I need to be told the names of 'things'. I do not know what "backlight" is.

Thanks,
Paul

[vinceroger69]

Re: Samsung LN32A330J1D Problems

backlights is either the ccfl or leds that light up from the back of the lcd panel usually you will see in a dark room some white light on the tv screen or if you look at the back of the tv you can usually see holes in the metal tv chassis you can see white light shining through which means the backlights are working.

[gitano]

Re: Samsung LN32A330J1D Problems

There are two "lights" that come on when the power cord is plugged in. One is the red LED in the on-chassis power button located bottom center of the front of the unit. The other is also red. It can be seen from the rear of the unit only. It is inside the black plastic connector for the "Digital Audio Out (Optical)" connection. It is the connector that is farthest left of the 15-pin D connector on the MB picture.

I turned all of the lights in the room out and cycled the on-chassis power button. The only light that can be seen is from the Digital Audio Out (Optical) connector. There are NO other lights visible. I did observe however, that the light in the Digital Audio Out (Optical) connector DID cycle on and off with the on-chassis power button. Were it not for these two lights, there would be NO indication of "life" in this device. It is COMPLETELY "dead". No sound, no whirring, no clicks, no 'ramp up', no lights, NOTHING on the screen.

Paul

[gitano]

Re: Samsung LN32A330J1D Problems

Not sure why this thread died on the vine, but nevertheless I have a new problem. I decided to just purchase replacement boards for both the PSU and the MB. The replacement PSU is identical in every way. However, the MB, while having SOME of the same numbers on the board and very similar, is NOT identical. I'd like some advice on whether or not the replacement board is usable in this TV.

Here is a picture of the two boards side by side:

The original board is on the right. Notice the circled areas. The extra connectors don't concern me. What concerns me is the missing plug on the replacement board.

Here are close-ups of the area of interest on each of the boards. First the original:


The replacement:


The circled area are the differences. It APPEARS that the smaller, 4-pin plug on the original is "dealt with" on the replacement, but since I don't know what that connector/plug is for, I don't know if the replacement is usable or not. I would assume the four wires going to that plug (red&black and yellow&black) are significant and can't be shorted, jumped or left open, but I'd like someone that actually knows what they do tell me that.

Thanks in advance,
Paul

[gitano]

Re: Samsung LN32A330J1D Problems

Was it something I said?

Paul

[Joseph cauchi]

Re: Samsung LN32A330J1D Problems

In your post #11 in the picture you said that you have 5.2vdc on the only pin.On the same post in the reading pin 3 which is the stby pin 0.0 vdc.this is the led on when the TV is pluged.Second thing Budm asked if you have 24vdc in post #10 and you said I am getting 24VDC on the correct pins in post #13 and in the same post this is your reading I get the following values for pins 11 through 14 on CN803:
11 - "A/D" = 3.48VDC
12 - "B/L" = 0.11VDC
13 - "P/D" = 4.44VDC
14 - GND = 0.0
You are showing that you do not have 24vdc

[Bahagu]

Re: Samsung LN32A330J1D Problems

The missing connector is just for the speakers