Re: Sharp LC-80LE661U - Power's off after 4 seconds.
Double checked and am definitely getting 4.5 - 4.8v on the ground pins when the TV is on (only for a few seconds until it shuts off, then it drops down to 0v).
Not sure exactly what you mean here. I tried using a 2k resistor (only thing I had on hand) between the ps-on and ground, then also between pnl_pow and ground, hoping it would turn on the LCD but didn't get any results.
Did some digging and I saw some power board and backlight issues, and some...
overlyAmbitiousSloth
Member
Last Activity: 02-23-2019, 04:45 PM
Joined: 01-27-2019
Location: Wasilla, Alaska
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Re: Sharp LC-80LE661U - Power's off after 4 seconds.
I may be missing something, but I've taken off the speaker mounts and bezel and am not seeing cables in the corners. The only cables I see are a couple pair of ribbon cables at the bottom of the TV. I've attached a couple pictures to give an idea of what I'm seeing. Unfortunately, I can't get the ribbon cables undone without completely disassembling the LCD housing. It looks like it would have to be loosened on all sides and then lifted up, probably just a a half inch, to disconnect those ribbon cables. Before...Leave a comment:
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Re: Sharp LC-80LE661U - Power's off after 4 seconds.
Well, I disconnected the t-con ribbon cables again (one at a time) and there is definitely not a uniform white displayed. In fact, it seems a heck of a lot worse than it did last night. I may have screwed something up in the mean time. I did have the power cable plugged into a six-strip and only powered off the strip between plugging and unplugging cables instead of fully disconnecting the power. Aside from that I can't think of anything else I did that would have effected it.
Oh, and I can't...Last edited by overlyAmbitiousSloth; 02-12-2019, 08:34 PM.Leave a comment:
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Re: Sharp LC-80LE661U - Power's off after 4 seconds.
Yep, it does still shut off after 4 seconds regardless of which of the t-con ribbon cables I had unplugged.
I've been doing some reading on feeding the t-con board a test pattern and am not finding any instructions on this type(G477FM05). I see some other boards have pins that can be jumped or shorted but I don't see anything on this board that screams 'bridge me' (I also don't really have a clue what I'm looking for, just comparing to the pictures in this post [url]https://www.badcaps.net/forum/showthread.php?t=26790[/url]...Leave a comment:
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Re: Sharp LC-80LE661U - Power's off after 4 seconds.
Thanks for the heads up. I'll double check to make sure I'm reading the proper pins when I get home this evening.
I can give it a shot, doesn't sound too complicated. Out of curiosity, is there any sort of guide hanging around for this (I've run through some of the guides on here and they're great, just haven't seen anything on this).
I've got a couple more pictures attached. Some of them show this banding effect, some of them don't....Leave a comment:
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Re: Sharp LC-80LE661U - Power's off after 4 seconds.
I see the following labels on the pin label for the cable between the mainboard and the powerboard:
PNL12V
GND
UR13.2V
UR13.2V
GND
GND
PS_ON
PNL_POW
NC
NC
ERROR
STB
Would it be the PNL_POW pin that I need to short to ground?
When taking power readings earlier I saw 5V on that pin. What type of resister would I need to use? Or, could I short it directly to one of the GND pins above...Leave a comment:
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Re: Sharp LC-80LE661U - Power's off after 4 seconds.
Tried but didn't turn on when I applied power. This may be a stupid question but is there a pin on the powerboard I can short to ground or something to feed it a 'power on' signal?
When I disconnected the large ribbon cables, one at a time, and powered on half of the screen was solid white (pictures attached).
For shits and grins I started disconnecting different cables, one at a time, and powering back on. Wifi, IR receiver, speakers, button pad, data cable...Leave a comment:
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Re: Sharp LC-80LE661U - Power's off after 4 seconds.
Is that a common symptom of a dead/dying main board? If so, is it even worth troubleshooting components on the board or just replace the whole thing?
Thanks for the suggestion budwich, I'll give this a shot as soon as I get home this evening and check back in with results.
Thanks for the suggestion nomoresonys, I'll give this a shot as soon as I get home this evening and check back in with results....Leave a comment:
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Re: Sharp LC-80LE661U - Power's off after 4 seconds.
My bad, didn't even think to do that (I've attached a picture of the power board that lists pin names, not sure if I'm reading it properly but I've referenced the PIN names in the left column)-
TV OFF/Stand-By
PNL12V - 0.3v
GND - 0
UR13.2V - 1.214v
UR13.2V - 1.213v
GND - 0
GND - 0
AC_DET - 0
BU5V - 5.04v
PWM1 - 0
DIM - 6.4v
OFL - 0
PWM2 - 0
TV ON – power applied
PNL12V - 11.88...Leave a comment:
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Sharp LC-80LE661U - Power's off after 4 seconds.
Howdy Folks,
This is my first time posting with an issue so I'm including as much info as I can (whether it turns out useful or not). I don't have any experience troubleshooting LCD TV's so I'm hoping someone out there can give me some tips or maybe point me in the right direction (even if its a 'RTFM nuub' if there's a link attached).
I've got a Sharp LC-80LE661U model TV that powers on, displays the SHARP logo and then promptly turns off after about 4 seconds. There isn't anything displayed onscreen other than the logo. I've tried button combinations to perform a factory... -
Re: New Members - please post your introductions here
Howdy Again,
After putting my most generic post I noticed that people are actually writing things about themselves. So, I figured I'd come back and follow suit.
I fix things. Born and bred Alaskan. Grew up in a house that threw stuff away when it broke and never liked the idea of disposable things, especially expensive ones (washers, dryers, fridges, transmissions, breaks, phones, computers... lots and lots of computers (kinda my day job), lights, remote control toys, vacuums, heaters, generators, lawn...Leave a comment:
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Re: New Members - please post your introductions here
Howdy Folks,
New to the forum and looking to get some assistance fixing a Sharp LC-80LE661U that I inherited. I hate throwing money at parts unless I know for sure there toast. Just throwing this message out there so I can get the necessary post points before I do a full write up on what problem I'm having and the troubleshooting I've run through already.
Looking forward to being part of the community and picking some brains on the proper ways to fix things... instead of just blindly stumbling through things...Leave a comment:
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