Re: Magnavox 42MF521D/37 - Dead
You can do a "smoke test":
https://www.youtube.com/watch?v=Xhqw...g&feature=plcp
You can do a "smoke test":
https://www.youtube.com/watch?v=Xhqw...g&feature=plcp
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Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
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Re: Magnavox 42MF521D/37 - Dead
That is great I haven't seen that before! I will try that..Comment
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Re: Magnavox 42MF521D/37 - Dead
Tom I pulled L5001 just for fun and still have that short on the OUT pin of 7003, and the other side of 5001 0.06 ohms. Multiple problems?Comment
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Re: Magnavox 42MF521D/37 - Dead
Pull the diode too and test. The IC itself could still be damaged but in a way that makes the rest of the board look shorted. I had this once with a DC-DC converter. It's really weird because there's no MOSFET between OUT and GND but some parasitic diode forms instead.Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
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Re: Magnavox 42MF521D/37 - Dead
Did that and no change.. Pin 3 INH has short to ground too though. Think I need a new main boardComment
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Re: Magnavox 42MF521D/37 - Dead
INH -should- be low. Low turns it on. Though if the IC is fooked, then it may have multiple shorts from being cooked.Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
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Re: Magnavox 42MF521D/37 - Dead
You think I should just try the new IC? I am concerned that I have 0.06 ohms to ground after the coil 5001 although that it looks that it is still tied in to the FB pin of 7003..Comment
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Re: Magnavox 42MF521D/37 - Dead
FB goes through resistors so it can't be that unless the resistors are shorted (I would doubt it.) Try the IC first, it is the most likely cause.Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
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Re: Magnavox 42MF521D/37 - Dead
I will. Kinda mangled the 5001 coil removing it but it should be OK.. Will let you know..Comment
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Re: Magnavox 42MF521D/37 - Dead
OK I just reinstalled the new 7003 IC regulator. And I do not have L5001 installed. I'm still not getting the 12v OUT. Now it was not easy removing the old IC and I lost pads 2 and 3 from the board but I was still able to solder to pad 3 and it looks like pin 2 is not used. I do have the 17v input. Is there anything else I need to look at? I didn't reconnect inverter and tcon boards while testing it but it should still give out the 12v correct? Or do I need the coil installed in order for the FB circuit to work the chip?
Update: Yes obviously coil needed to be in the circuit, and now I have the 12V and TV is powering up. I need to reinstall everything now to see if it's all good.Attached FilesLast edited by kevinm34232; 11-20-2012, 04:23 PM.Comment
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Re: Magnavox 42MF521D/37 - Dead
You figured it out before I got the chance to reply. good luck.Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.Comment
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Re: Magnavox 42MF521D/37 - Dead
Well reinstalled everything and I got a picture for a second and then it shut off can smell burning... Now Im getting 15v instead of the 17v off the PS board and it won't come on again.. It's such as hassle working on this thing the way it all goes together, I have to unscrew it again..Comment
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Re: Magnavox 42MF521D/37 - Dead
Looks like 7003 may have burnt up again had some white grease on top of there is a brown mark on the corner close to pin 8, looks like that's where it was damaged before. Now the input is a little low (15v compared to 17v) and no output.
16.5v off PS board when not connected to main board so it's being loaded down. Without L5001 in circuit before I had a 0.04 reading at 200k ohms on the 12VS does that indicate a problem down the line?Last edited by kevinm34232; 11-20-2012, 05:26 PM.Comment
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Re: Magnavox 42MF521D/37 - Dead
There might be excessive load -- did you do the short test as in the video?Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
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Re: Magnavox 42MF521D/37 - Dead
Yes I did, there is bulbling from freeze spray at 7003 where it looks burnt.
Is it odd that it wouldn't blow the fuse right out of that regulator?Last edited by kevinm34232; 11-20-2012, 05:33 PM.Comment
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Re: Magnavox 42MF521D/37 - Dead
Remove that IC, then try it over the rest of the board -- something else may be faulty.Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
For service manual, schematic, boardview (board view), datasheet, cad - use our search.Comment
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Vizio e601i-A3 - Has Sound and Display, But No Backlight - Bad Power Supply Board or Bad LED Bulbs ?I was given this TV from my great uncle. He said it just wouldn't turn on one day out of nowhere, replaced the TV, and gave it to me to possibly fix and use for myself.
Upon bringing it home and plugging it up, it showed a standby light.
I powered it on and without a flashlight, the display showed the "V" but the lighting is very dim, but visible.
The screen seems to blackout and stay black, but with a flashlight I can see the display.
With my Playstation 4 connected via HDMI, and running a game I can hear sound.
Assuming... -
Hi everyone,
I have a NM-A321 board that is dead, with no power at all.
When I received the laptop, the +5VPMIC line was shorted. Removing the PU3 (ISL95905) solved the short, so I ordered and replaced the ISL.
With the new ISL, the short is gone, but still no voltages at all. I measured the following rails:- +3VALW
- +5VAUX
- 1.2VSUS_PWRGD
- 3VALW_PGD
- 1.05VAUX_PWRGD
Additionally, the ISL95906 (PU3) is not getting any voltage on the VIN rail.
The only place on the board where I find any voltage is on the first MOSFETs, specifically:... -
All left and right refers to looking from rear of TV (or looking from front with TV upside down)- TV came with vertical bars and no image. Found faulty TVS on left buffer board. Also replaced T-Con (may have damaged the original while hot air removing components, board has slight warp) and have full image but few horizontal lines on the screen. Some of the lines appears to be 2 pixel tall while others are 1 pixel tall.
- Disconnecting left and right buffer board potentially reveals problems on both sides with different signals (unless this T-Con require jumper like Samsung FB_TRDY1&3) Fault
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Hello, the DSLR has heavyly fallen. It is dead : no sign of life and display nothing.
When it worked, it always displayed a card present state on LCD display, even when the battery is empty it display a empty battery symbol.
I found a dead fuse, I replaced it and a mosfet burnt, I changed it and another fuse burned. Nothing burned after. And I can't find any short circuit anywhere, it's weird.
Now, I try to understand how it works.
There is two boards (the little one on pictures has no component) : the first is a « power board » : managing... -
Hi everyone,
Im looking for some advice regarding my Samsung UE55MU8000 TV with main board model BN94-11606C. The TV suddenly stopped turning on and now shows no signs of life at all not even the standby light at the bottom.
Initially, I suspected an issue with the PSU, so I took it to a repair center. They tested it and confirmed that the PSU works perfectly, even on other TVs. Based on that, I started investigating the main board.
I disconnected the main board from the PSU, and the backlight turned on, which seems to confirm the main board is the issue....
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