YSUS test on a Vizio P50HDM

[firepac493]

Hello fellas
New to the board so be kind.
I have been doing tons of research online in trying to fix my parents Vizio P50HDM. My parent were watching TV and say that the screen went black...no pop. I took the rear panel off and found one of the 4amp fuses was bad on the YSUS board. Any recomendations on a repair or a supplier here in the Phoenix area. I can install myself if need be. I also checked the voltages on the power inverter board all checks well. VA+ pins have 190vdc +-...is this normal?

[PlainBill]

Re: YSUS test on a Vizio P50HDM

The blown fuse indicates the problem is the Y-sustain. Rebuilt replacements are available for about $110-$120 with exchange. Research would indicate if replacing Y buffers is also recommended.

The two YPPD modules would cost $70 if you want to do the repair yourself.

PlainBill

[Kb7aVdTcAa3p]

Re: YSUS test on a Vizio P50HDM

Hello,
I am experiencing similar problems with my Vizio P50HDM it just shows no picture.
The 4amp Fuse for Vs+190V is blown too, but additionally a 250V 150µ cap on the Y-Sus board is leaking elektrolyte.
I already checked the voltages they seem OK: Va+ 60V Vs+190V.
How can I test which parts failed?(I would like to avoid replacing the whole YSUS-board)

[mockingbird]

Re: YSUS test on a Vizio P50HDM

The blown fuse indicates the problem is the Y-sustain. Rebuilt replacements are available for about $110-$120 with exchange. Research would indicate if replacing Y buffers is also recommended.
The two YPPD modules would cost $70 if you want to do the repair yourself.
PlainBill

Why would you need two YPPD? Do you also have to replace one on the Z sustain? Have you ever replaced a YPPD? What is the best way to remove it? I'm thinking wicking away the solder from each individual hole... Is there a better way?

[PlainBill]

Re: YSUS test on a Vizio P50HDM

Why would you need two YPPD? Do you also have to replace one on the Z sustain? Have you ever replaced a YPPD? What is the best way to remove it? I'm thinking wicking away the solder from each individual hole... Is there a better way?

The recommendation is to replace both of them. Probably because they interact and one shorting can damage the other.

I have never replace a YPPD, but I have replaced the hybrid used on the LG 42PC3D-UD (and countless others using the same panel). Solder wick won't begin to do the job, Grasshopper. There are very heavy ground and power planes on the board.

One method that worked for me: Heat the leads of the hybrid with a heavy duty soldering iron (60 watt recommended) and add Chip-Quik to each lead of the hybrid. Protect the area outside of and between the rows of pins with several layers of aluminum foil. Fasten the board to a piece of plywood with a hole slightly larger than the hybrid cut in it. Similarly protect the plywood with several layers of aluminum foil. Fasten the plywood to a sturdy bench - preferably outdoors. Rig a handle to grasp the hybrid by the heat sink. Carefully heat the bottom of the board with a heat gun on it's low setting, keeping the heat gun moving. When the solder on the upper surface starts to melt CAREFULLY lift the hybrid by it's heat sink. Using a heavy duty soldering iron, heat each hole and use a dissecting pick to force the solder out.

On one attempt I tried skipping the Chip-Quik. I keep the board on hand to remind me that I'm not infallible.

Other methods have been reported to work.

1. Use a screw driver to break the ears on the hybrid that hold the screws holding it to the heat sink. Cut the pins on the hybrid. Using a heavy duty soldering iron, remove the pins one at a time, using a steel needle to clear the solder from each hole.

2. Obtain two old fashioned tinner's soldering irons (these are square rods of copper roughly 3/4" x 3/4" x 3" attached to an iron shaft, which goes into a wooden handle). Hacksaw a groove lengthwise ~3/16" deep on one corner of each iron. Heat the irons and fill the groves with solder. While the irons are hot, use them to simultaneously heat each row of pins until the solder melts and the hybrid (or YPPD) can be removed. Again, use a steel needle to clear the solder from each hole.

PlainBill

[mockingbird]

Re: YSUS test on a Vizio P50HDM

The recommendation is to replace both of them. Probably because they interact and one shorting can damage the other.

Bill, I've been reading Coppel TV Repair just to get a better idea of what I'm getting into. The model like I've stated before is an Akai PDP4273M 42". I actually managed to download the service manual a while back (So I can figure out how to open it. It's got tons of screws).

He's agreeing with what your saying. His latest entry, from this month, is somewhat dumbed down and understandable for people like me:

Which is to explain and underscore that functionality of one sustain is not affected by the other.
Still, it is affected by something completely different, which suggests
It may still be better to service or replace both sustain boards at the same time.

I have never replace a YPPD, but I have replaced the hybrid used on the LG 42PC3D-UD (and countless others using the same panel). Solder wick won't begin to do the job, Grasshopper. There are very heavy ground and power planes on the board.

Isn't a YPPD and a Hybrid the same thing? I'll try the acid flux to aid the wick's flux. I've done this before with a copper coil, but I was pulling the coil off very hard while I was melting.

Thanks for your help. I will no doubt end up using one of your methods. I'm gonna see if my local electronics shop has any chip quick.

One more thing... You recommend replacing the YSUS Buffer.... Do you think the caps go south on these or is it something else that is difficult to diagnose?

[PlainBill]

Re: YSUS test on a Vizio P50HDM

Bill, I've been reading Coppel TV Repair just to get a better idea of what I'm getting into. The model like I've stated before is an Akai PDP4273M 42". I actually managed to download the service manual a while back (So I can figure out how to open it. It's got tons of screws).

He's agreeing with what your saying. His latest entry, from this month, is somewhat dumbed down and understandable for people like me:



Isn't a YPPD and a Hybrid the same thing? I'll try the acid flux to aid the wick's flux. I've done this before with a copper coil, but I was pulling the coil off very hard while I was melting.

Thanks for your help. I will no doubt end up using one of your methods. I'm gonna see if my local electronics shop has any chip quick.

One more thing... You recommend replacing the YSUS Buffer.... Do you think the caps go south on these or is it something else that is difficult to diagnose?

You are correct, the YPPD is a hybrid. There are a number of them used on various LG and Samsung (and possibly others) Y and Z Sustain modules. The are sometimes refered to as IPMs. I've never dealt with a 50" LG plasma.

The technique used to remove them will work on any EXCEPT the Samsung. Those boards are designed so the heat sink can be easily removed, so the 'cut the pins and extract' method works well. If I were removing them regularly I would rig up a 'branding iron' using a pair of notched copper bars, a support jig, a blowtorch, and a thermocouple. With a little experimentation it should be possible to heat the tool to the proper temperature, then pull the module in a fraction of a minute.

PlainBill