Re: Emerson/Funai LF46EM4 no image
Model type B, starting around pg. 50.
ALSO; just did some more searching for a Magnavox 46" and I came across a post from budm that linked a 46" set...though it doesn't reference Emerson as a model. I may look at that too.
[url]https://www.badcaps.net/forum/attachment.php?attachmentid=152278&d=1487816733[/url]Re: Emerson/Funai LF46EM4 no image<b...more searching...
Josh86
Member
Last Activity: 06-19-2018, 01:52 PM
Joined: 06-03-2018
Location: UP, Michigan
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Re: Emerson/Funai LF46EM4 no image
Could I just start checking voltages on the ICs as a method to determine whether or not components might be the cause of failure? I don't have a schematic for this particular set, but I'm working off one that seems nearly identical....Last edited by Josh86; 06-19-2018, 11:49 AM.Leave a comment:
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Re: Emerson/Funai LF46EM4 no image
I'm unsure, but is there anyway to test an in-circuit cap with a multimeter? Is disconnecting the cap or using an ESR the only way?Last edited by Josh86; 06-19-2018, 10:03 AM.Leave a comment:
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Re: Emerson/Funai LF46EM4 no image
Thanks; it's good to at least hear another opinion on it. My wife told me to immediately throw it away (usually she's always right).
Before replacing the backlight, the board/display was working, but shutting down because an entire row was out. Sometime during the breakdown I must have unseated a cable or shorted something because I was getting bad readings out of the LVDS to the TCON (and the cable was was hot to the touch on the supply line/pins). That problem is since gone, but now I get nothing on the display.
What...Last edited by Josh86; 06-19-2018, 09:24 AM.Leave a comment:
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Re: Emerson/Funai LF46EM4 no image
Took the aluminum frame off the bottom of the display to look for visible damage to the LCD board but I could see none. I tested caps that my leads were small enough to get at and the one's I checked were OK. LCD board also has labeled test points; but I did not take measurements.
The FETs on my old T-Con were OK.
My new T-Con arrived and I hooked it up only to the mainboard. I got the same exact voltage readings on the new T-Con. Afterward I connected the LCD and still no picture.
Still unsure if the panel...Last edited by Josh86; 06-19-2018, 08:03 AM.Leave a comment:
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Re: Emerson/Funai LF46EM4 no image
Haven't been able to look at the set for about a week but...
I'm ordering a t-con board because they can be had for ~$10.
I went through the troubleshooting flowchart on a 39" Funai (all the connectors/pinouts identified the same) and I end up with the result that it's either the mainboard or a bad panel. The "no video" tests had me check for certain voltages at specific pins on both the mainboard and connection to the t-con. They ended up coming out as expected which leads to the suggestion of replacing...Last edited by Josh86; 06-15-2018, 09:16 AM.Leave a comment:
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Re: Emerson/Funai LF46EM4 no image
I can certainly order a T-Con, though I'm concerned it may not work because I'm not getting any audio output over composite/component. I can't find a service manual for these Funai 46" sets (either Emerson or Magnavox) but I looked at some schematics and block diagrams from both 32" and 39" Funai sets and I don't see anything going over the LVDS to the T-Con that has much to do with the audio interface on the L/R inputs.
I guess I'd just like my concerns to be proved wrong or explained -- because a $20 T-Con would be...Last edited by Josh86; 06-08-2018, 01:02 PM.Leave a comment:
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Re: Emerson/Funai LF46EM4 no image
Which voltage readings do you suspect are abnormal from expected voltage? This way I can retest and confirm before before I order a new T-Con board.
Thanks!...Leave a comment:
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Re: Emerson/Funai LF46EM4 no image
Remeasured and the CPV testpoint area reads as follows:
CPV3 = 2.407 (taken the day before)
CPV4 = 2.37 V
STV2 = 2.37 V
CPV1 = 2.37 V
(?) USI_SYNC = 1.77 V
CPV2 = 2.11 VLeave a comment:
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Re: Emerson/Funai LF46EM4 no image
So looking at the reads I thought "where is CPV1 if I'm reading CPV2"? I then realized I actually never read CPV2; I used the top test point which was likely for CPV3. I completely ignored all the rest of the labels and just looked at that highlighted box -- whoops.
If you really need CPV2 (I assume it's an important signal), I'll have to wait until I'm back home to check it out and I'll record all those values on those test points. In the meantime, if there are any other points you want me to check (either...Last edited by Josh86; 06-07-2018, 06:49 AM.Leave a comment:
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Re: Emerson/Funai LF46EM4 no image
Reattached marked up image with voltage reads....Leave a comment:
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Re: Emerson/Funai LF46EM4 no image
I've tried checking for sound with an input source but with no luck.
Is it possible it's still the T-Con board in this situation or is that a sure sign it's the mainboard? I don't know anything about how the logic works between any of the chips/boards without seeing a block diagram (and even then I may not understand it), but I wonder if the mainboard wants to see/confirm some output from the T-Con coming back for everything to work (including audio output). If anyone knows of a link to a service manual for this line of units, that'd...Last edited by Josh86; 06-06-2018, 01:15 PM.Leave a comment:
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Re: Emerson/Funai LF46EM4 no image
Attached again. Let me know if you want detail of anything and I might be able to use a DSLR to get a closer high res pic. Would it be worth checking for audio again on an input since I'm getting normal voltage to the TCon now?...Last edited by Josh86; 06-05-2018, 12:26 PM.Leave a comment:
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Re: Emerson/Funai LF46EM4 no image
Half of the panel completely white, the other half black with one connected. Same with both cables. When both are connected it looks just the same as when they are both disconnected (black screen).
Attached main and supply board pics -- couldn't do it from wife's old iPad earlier. Attachments from photos on iOS just automatically name every file "image" when uploading and overwrites multiple files, just leaving you with the last uploaded....Last edited by Josh86; 06-05-2018, 05:48 AM.Leave a comment:
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Re: Emerson/Funai LF46EM4 no image
Yeesh, sorry, even I know better you can't get a reference to anything like that. Not thinking. I took some circuit analysis and DSP long ago but never really used it. This is about as much practice as I get...when I feel like trying to fix some broken thing a couple times a year.
So might have to take a step back.
I removed the TCon board for better lighting and access with my multimeter. Rung out pins (1 and 4 connected to fuse). Have 12V on pins 1 and 4 out of mainboard to end of LVDS. Hooked TCon...Leave a comment:
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Re: Emerson/Funai LF46EM4 no image
I do not have any voltage across F1 when the TV is powered. I get ~3V when I measure from either side of the fuse to the chassis and a little less to a ground on the T-Con board. I have continuity across the fuse. Everything on that board is surface mounted and I didn't see any other fuses on that board. Image attached.
I noted that the LVDS cable feels pretty hot on the pin 1 side (unless that's normal, cable is rated for 105 C). It's not inserted backwards....Leave a comment:
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Emerson/Funai LF46EM4 no image
(LF461EM4) Initially this 46" LCD was shutting down on me after the Emerson logo and channel display. Through the info of another thread here I decided to look at the backlighting and found that the center row of LEDs were out (LG branded). Bought a Samsung branded replacement on eBay and it works. It no longer shuts off with a blinking front LED sequence.
However, at some point during disassembly or reassembly of the front panel I must have done something because the display no longer shows anything. My first thought was I damaged some part of the LCD or connectors...but then... -
Re: New Members - please post your introductions here
Tv problems led me to this site and I'm already seeing there's a lot of great information and helpful people here. I like to be a DIY kind of person fixing my house, cars, toys, etc...but I feel more at home with computers and electronics.
Hoping anything I come across or bring up will help others in the future as I often get information for old threads.Leave a comment:
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