Re: Lenovo thinkcenter mini m93 hit by lightning
Apologies to sputnikoff for thread jumping, but I think I have a similar issue not the same, however my knowledge of the system is limited and possibly incorrect.
My assumption is the 5v / 3v standby voltage is not there. Be that something failing on the supply line or something pulling the output / input to a fet down. There also seems a SF1 fuse in close vicinity to the ethernet controller which I (maybe incorrectly incorrectly) assume would blow in this case.
Out of interest - on the basis the unit dies from...
RobbieC
Member
Last Activity: 11-15-2023, 03:39 PM
Joined: 09-12-2013
Location: Derby
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Re: Lenovo thinkcenter mini m93 hit by lightning
Sod's law - IS8XT. Hopefully have more time and patience to work backwards. Do have access to working units though to assist and swap parts.Leave a comment:
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Re: Lenovo thinkcenter mini m93 hit by lightning
Did you find a resolution to this issue as I have a very similar one. I have 2 units which appear to have died post lightening but are completely dead. I have no 5v from U10 (PK5048A) but have 10v going to it but cannot trace where it is switched from.
Again this appears to be a standby voltage which feeds ethernet as standby allowed network leds flashing when powered down on the good board. Any schematics floating for this board ?Leave a comment:
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Re: LG 47LN578V - Brief Backlight flash on power up.
The shorted ones are fine (to a point) the open circuit ones will cause the whole string (or both) to fail to light as the psu self check knows there is an issue and switches off.
Find the open circuit led and bridge it to get partially working string which works enough to view.
Failing that you have to buy a whole new set.Leave a comment:
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Re: LG 47LN578V left hand column of screen flickering darker at regular rate
It appears to be the left 1/4 of the screen but the whole column from top to bottom.
Do you mean the led back light as it cant be that due to it running horizontally and in 2 strings which would mean the whole string would dim which would be visibile accross the whole of the screen.Leave a comment:
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Re: LG 47LN578V left hand column of screen flickering darker at regular rate
[url]Http://1023.co.uk/MOV_0268.mp4[/url]
[url]Http://1023.co.uk/MOV_0269.mp4[/url]
Video not great but you can see the effectRe: LG 47LN578V left hand column of ...see the effectRe: LG 47LN578V left hand column of screen flickering darker at regular rate
[url]Http://1023.co.uk/MOV_0268.mp4[/url]Leave a comment:
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LG 47LN578V left hand column of screen flickering darker at regular rate
My LG 47LN578V developed an annoying 'feature' yesterday.
An approximate 30cm (1 foot) column on the left of the screen consistently darkens, then returns to the same level as the rest of the screen at a rate of just under 0.5 Hz.
The picture quality of fine just the light level.
This is the set which had a full led backlight replacement done at Xmas and knowing how the circuit works it obviously isnt that!
Thoughts ? -
Re: LG 47LN578V - Brief Backlight flash on power up.
Good find! So do have / plan to replace all 54 then - I think this is good practice IF you can refit the lens correctly as if the light colour is not the same as the original it is not noticed.
My observations though:
Colour temp of originals i thought was more in range 6500-7000k as I compared a few i replaced (rated 6500) against the originals and the originals were a touch whiter.
I very much suspect they will be a fixed voltage & current rail with varying duty cycle for dimming. Obviosuly this may alter...Leave a comment:
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Re: LG 47LN578V - Brief Backlight flash on power up.
The joys of tinkering!! My viewpoint being I am messing with my set as a project and not as a business and working on someone else's tv!
I refitted all the 'dodgy' lens (some were very poorly aligned) using my heat gun from below to soften the plastic. I was pretty pleased with the end result at they were all central to to led with only the height varying (true height is around 1mm) but not by much! I also noted all the 'dead' led which I had replaced with new ones but wrong colour, removed them and shorted the pads....Leave a comment:
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Re: LG 47LN578V - Brief Backlight flash on power up.
For starters, this is my tv I have sourced and wish to repair for me. I quite like having it as my main tv so if that can be done for sensible money then I will. The background I have is that these are middle of the road tv's produced with corners cur, one being the led's which seem a very common fault. This is not helped by default backlight being set to max which reduces the life significantly.
Now to replacment led's, I had also assumed the ones @flocko was selling were used ones as per all the others on ebay (the link...Leave a comment:
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Re: LG 47LN578V - Brief Backlight flash on power up.
Hmm thats not bad at all - works out at under £7 per strip for new led's. Worst case scenario is buy a set and sell the old ones on.
@Flocko - yeah hindsight is a wonderful thing as I was unaware of how critical the lens is. Bit of trial and error now needed for a spacer / washer to get the height and alignment right. Replacing one / all with used led's isnt a viable option imho.
If i was to fully rewind, i would have just pulled all the dead led's i had previously and short them as they seem to be the...Leave a comment:
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Re: LG 47LN578V - Brief Backlight flash on power up.
Just looking at that - seems semi reasonable if new but be interested to see what anyone with an account gets. I guess that must be the LG standard replacement - now just need a friendly one... !
[url]http://www.chsinteractive.co.uk/electrical-components/special-offers/led-array-screen-assy-47-x12-strips-television-lg-47ln613vzbbekyljg-click-here-for-more-info.htm[/url]Re: LG 47LN578V - Brief Backlight fl...emi reasonable...Leave a comment:
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Re: LG 47LN578V - Brief Backlight flash on power up.
Funnily enough that is exactly my experience! So my previously fixed tv died again. Stripped and saw no obviously (new) dead led but 1 string was obviously not flashing at all at startup. Narrowed down by swapping the r1 r2 l1 l2 combos until the other string failed. Then popped off the led lens to work along. Curiously, on my multimeter in continuity mode which beeps, i can just manage to get a working led to light which helped no end identify the issue. One of the led's which had previously failed shorted had popped and was...Leave a comment:
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Re: LG 47LN578V - Brief Backlight flash on power up.
So this is the footprint. Was hoping for more 'side' access to the pad but looks as though it needs to be sat on the pad from above.
I intend to be using a hot air station from below so shall see!
It appears there are 2 bits on each pad which wrap up the side of the led which you could use for soldering but they are thin and wouldn't like to guarantee to be a good enough connection....Leave a comment:
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Re: LG 50LA6230 backlight repairs
? afaik all of the strings using in tv's are in series which is why the whole string dies if one goes open circuit. Would be some serious current if in parallel too!
Shorting only works IF in seriesLeave a comment:
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Re: LG 50LA6230 backlight repairs
I did the same thing but just shorted the LED. There is enough tolerance in the supply to allow for missing individual units (mine also had 8 failed led's too but had failed shorted so didn't take down the string).
Ideally, long term fix is find suitable drop in repalcements (for one or all led's)Leave a comment:
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Re: original XBOX V1.6 no power
Does it try to power up 3 times ? I remember them doing that if someone had screwed up modding them. lpc looks clean though so looks 'standard'.
Out of interest what did you swap to prove its the MB ?Leave a comment:
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Re: LG 47LN578V - Brief Backlight flash on power up.
I was dubious about the footprint for the 3535 too! Unfortunately I couldn't find too many alternatives for a similar spec. My interpretation was that the ideal layout would have the pads with only a small gap (0.6mm) between but that they should be ok with the existing ones..... I ordered them yesterday with delivery this morning so will see. For only £7 (USD 10) I can live if they wont fit
Leave a comment:
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Re: LG 47LN578V - Brief Backlight flash on power up.
i had a good look through them all - all similar to this [url]http://www.ebay.co.uk/itm/50x-XENON-WHITE-3528-PLCC-2-SURFACE-MOUNT-ULTRA-BRIGHT-LEDS-PLCC2-SMT-SMD-/310402822610?hash=item48457331d2:m:mVNycxvFjHHYtHEAF0DjH8A[/url]
my concern was all the forward current were rated at 20mA max which i'm guessing is much lower than spec.
Personally I am leaning to these @ 200mA [url]http://uk.rs-online.com/web/p/products/897-8737/[/url]
or maybe these at @ 300mA [url]http://uk.rs-online.com/web/p/products/897-8784...Leave a comment:
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Re: LG 47LN578V - Brief Backlight flash on power up.
haha thanks - i'm guessing that's your auction seeing as they are based in Dover as you are, although I was led to believe some of the vestel strips were different sized led.
For me - using a 2nd hand led / strip from an already failed or damaged set isnt a full term fix, neither is it really cost effective.
For example, I picked up a cheap damaged set which had 9 failed led on over several strips. The strips were around 25 - 30 GBP each which had either 4 or 5 led on each one.
This has failed again so I am maybe...Leave a comment:
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