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Old 02-18-2011, 01:02 AM   #61
retiredcaps
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Default Re: HannsG HW173D dead. Recap = new fault.

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Originally Posted by Rtech View Post
Now thats the one,combined PWM and FET....
Ahh, that makes sense now.

Looking at page 14 and figure 24, I'm going to assume pin 1 is getting 160V DC.

Pin 2 is GND.

Pin 3 is vcc. C123 has already been replaced, but there is still fluctuating voltage across that cap.

Pin 4 is feedback via optoisolator.

So, on pin 3, the voltage is coming from the tertiary winding. It goes through R104 and D102 in figure 24. Here are the possibilites (if my schematic reading skills have improved - and using the schematic reference designations).

a) R104 is bad. I believe R104 corresponds to the resistor just right of the big Capxon cap. Unsolder one leg of R104 and measure the ohms and compare it to the band color.

b) D102 is bad. I believe D102 corresponds to D110 on the power board. You can test this "in circuit" to see if it is shorted. Put your multimeter on diode test. Put black on one side and red on the other. Record reading. Now reverse probes and record 2nd reading.

A good diode should measure between 0.4 and 0.7V one way and 0L or "1" the other way.

It might also be worth testing the diode (D12?) just above the C123 cap in case I picked the wrong diode on the power board.

c) If R104 and D102 (D12?) are okay, then the chip itself is bad.
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Old 02-18-2011, 07:48 AM   #62
slvfox2008
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Default Re: HannsG HW173D dead. Recap = new fault.

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Originally Posted by retiredcaps View Post
Ahh, that makes sense now.

Looking at page 14 and figure 24, I'm going to assume pin 1 is getting 160V DC.

Pin 2 is GND.

Pin 3 is vcc. C123 has already been replaced, but there is still fluctuating voltage across that cap.

Pin 4 is feedback via optoisolator.

So, on pin 3, the voltage is coming from the tertiary winding. It goes through R104 and D102 in figure 24. Here are the possibilites (if my schematic reading skills have improved - and using the schematic reference designations).

a) R104 is bad. I believe R104 corresponds to the resistor just right of the big Capxon cap. Unsolder one leg of R104 and measure the ohms and compare it to the band color.

b) D102 is bad. I believe D102 corresponds to D110 on the power board. You can test this "in circuit" to see if it is shorted. Put your multimeter on diode test. Put black on one side and red on the other. Record reading. Now reverse probes and record 2nd reading.

A good diode should measure between 0.4 and 0.7V one way and 0L or "1" the other way.

It might also be worth testing the diode (D12?) just above the C123 cap in case I picked the wrong diode on the power board.

c) If R104 and D102 (D12?) are okay, then the chip itself is bad.
A) I cannot find a R104. I have a R101(near big cap), 102, 113, & 114.

B) Have not tested yet but D110 looks bad.
I have a D120 but not a D12
Going to start testing now.
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Old 02-18-2011, 08:45 AM   #63
slvfox2008
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Default Re: HannsG HW173D dead. Recap = new fault.

The test is over for the FSC part. Shorted out the part when testing pin1 & 2! Before that pin 2 & 3 was fluctuating between 8 and 11.


Before that happened D110 was reading .483 and OL. Part D120 was reading .480 & OL.

Where do I go from here?
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Old 02-18-2011, 09:37 AM   #64
slvfox2008
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Default Re: HannsG HW173D dead. Recap = new fault.

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Originally Posted by slvfox2008 View Post
The test is over for the FSC part. Shorted out the part when testing pin1 & 2! Before that pin 2 & 3 was fluctuating between 8 and 11.


Before that happened D110 was reading .483 and OL. Part D120 was reading .480 & OL.

Where do I go from here?
Question, when testing D110 and D120, should I have power to the board?

If so D110 is reading .485 & OL. D120 is .002 & .002
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Old 02-18-2011, 09:44 AM   #65
el3ctroded
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Default Re: HannsG HW173D dead. Recap = new fault.

No, never test diodes with a board powered up.
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Old 02-18-2011, 11:29 AM   #66
retiredcaps
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Default Re: HannsG HW173D dead. Recap = new fault.

Quote:
Originally Posted by slvfox2008 View Post
A) I cannot find a R104. I have a R101(near big cap), 102, 113, & 114.
R104 is in the schematic. I was trying to find the corresponding resistor on your board. Often the schematic pcb designations are just samples and manufacturers can follow their own standards.
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Old 02-18-2011, 11:30 AM   #67
retiredcaps
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Default Re: HannsG HW173D dead. Recap = new fault.

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Originally Posted by slvfox2008 View Post
If so D110 is reading .485 & OL. D120 is .002 & .002
Never test diodes with power on. Remove D120 from the board and retest out of circuit.
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Old 02-18-2011, 11:31 AM   #68
retiredcaps
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Default Re: HannsG HW173D dead. Recap = new fault.

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Originally Posted by slvfox2008 View Post
Shorted out the part when testing pin1 & 2!
If you shorted it out, you will have to replace it obviously.
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Old 02-18-2011, 12:16 PM   #69
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Default Re: HannsG HW173D dead. Recap = new fault.

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If you shorted it out, you will have to replace it obviously.
Can you tell me where I can purchase one. Is there a chance that I have done other damage to the board. Is there a chance that this part was causing the other parts to fluctuate.
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Old 02-18-2011, 12:38 PM   #70
retiredcaps
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Default Re: HannsG HW173D dead. Recap = new fault.

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Originally Posted by slvfox2008 View Post
Can you tell me where I can purchase one. Is there a chance that I have done other damage to the board. Is there a chance that this part was causing the other parts to fluctuate.
1) Phone the suppliers using findchips to see when stock will be available. If not available, ask them what is an equivalent part.

http://www.findchips.com/avail?part=FSCM0465RG

2) You might have caused some other damage. Thus you might want to order 2 of the above PWM.

3) Yes, this part could have been bad and caused the fluctuating voltage. Now we will never know for sure.

4) Test the diode out of circuit. If it is bad, you can order a replacement at the same time.
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Old 02-18-2011, 02:59 PM   #71
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Default Re: HannsG HW173D dead. Recap = new fault.

I would like to thank all of you for your inputs and patience working with me. There are several other people experiencing the same problem and it would have been nice to have fixed this so they too could repair theirs. I am in the process of trying to locate a new semiconductor, but not having too much luck. Not many company's just want to sell you one without charging a ridiculous price.
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Old 02-19-2011, 02:36 AM   #72
Rtech
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Default Re: HannsG HW173D dead. Recap = new fault.

slvfox2008....where are you in th World ,as then perhaps members may be able to point you to a 'reasonable' supplier ??
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Old 02-19-2011, 06:50 AM   #73
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Default Re: HannsG HW173D dead. Recap = new fault.

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slvfox2008....where are you in th world ,as then perhaps members may be able to point you to a 'reasonable' supplier ??
usa
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Old 02-02-2013, 09:11 PM   #74
tanohack
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Default Re: HannsG HW173D dead. Recap = new fault.

Has been a long time now, but my monitor had the same defect, and the problem was simply the pins in the cable that were not enough contact pressure with your fingers to see the screen .. try ...try...
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Old 04-21-2013, 06:30 AM   #75
giovengi
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Default Re: HannsG HW173D dead. Recap = new fault.

i have the same board...
can anyone post values of
c307
r302
d303
thanks for any help
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Old 05-20-2013, 01:28 AM   #76
jfriends24
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Default Re: HannsG HW173D dead. Recap = new fault.

hello there! is this thread still active? i have the same lcd with bloated capacitor (C850), i replaced the bad caps but it keeps on blowing up...

the inverter board looks like this:
http://assets.shopjimmy.com/media/ca...M/IMG_4595.JPG

what else could be the problem? how can i test the circuit using fluke 8060a to know what causing the C850 to blow up? thanks in advance masters!
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Old 05-20-2013, 05:07 AM   #77
Lumberjack777
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Default Re: HannsG HW173D dead. Recap = new fault.

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Originally Posted by jfriends24 View Post
hello there! is this thread still active? i have the same lcd with bloated capacitor (C850), i replaced the bad caps but it keeps on blowing up...

the inverter board looks like this:
http://assets.shopjimmy.com/media/ca...M/IMG_4595.JPG

what else could be the problem? how can i test the circuit using fluke 8060a to know what causing the C850 to blow up? thanks in advance masters!
The most common cause for an electrolytic cap to explode after repair is if it was installed backwards. Those caps have polarity and need to be installed in the right direction. The printed circuit board usually has a circle on top for these caps. And one half is shaded, or has stripes, or similar. This is the negative side of the capacitor. (The side with the stripe on the cap goes on the shaded area of the circle)
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