LCD Monitor has rough screen with ripples

[Rasz]

its inside the panel case, usually under a flap

[rockblues]

Replacement boards - cables arrived.  Monitor plugged into power not PC - still distorted lines.

[rockblues]

its inside the panel case, usually under a flap

Video on replacing a TCon Chip (see video): https://youtu.be/CWL0Y8g-TMo

Rasz - Opened the LCD Panel - yes there is a flap. Had a Hex screwdriver small enough to do the job!! TCon Chip - HiMax HX8861-K 73DFCG 610NTAGC KRQQA 60497

How do I order a replacement chip? The panel is held by very thin connectors to this board - not good to replace the entire panel. What about the fuse? Must that be replaced as well?  How do you know if it's good or not?

Thanks.

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It's really sad that TCon chips / ribbons fail. Very inexpensive parts that are hard to find and difficult to replace.

What makes a TCon chip / ribbon fail - in normal use? One day working. The next day the entire investment is down the drain as one TCon Chip has suddenly gone bad.

DELL makes PCs / Monitors by sourcing parts. The suppliers ought to be held to a high standard of quality.

[mariush]

The chip may not be the issue.
Any of the tiny resistors and capacitors along that wide strip of circuit board can be faulty or not making a good connection to the traces on the board. On of the voltage regulators on that long board (looks like there's some on the left side in the picture but it's too low res to know for sure) could output an unstable voltage that could affect one of those ICs...

The problem may also be a poor contact between the film strips that come from the actual panel to the wide circuit board... those are almost impossible to fix by regular folks like you.
You can try to see if this is the problem by gently pressing on those strips of film / flat flex strips / whatever you want to call them as you're looking at the panel ... for example slowly drag your finger nail over the surface of those film strips and look at the screen and see if there's some changes.

[TERRA Operative]

You can try to see if this is the problem by gently pressing on those strips of film / flat flex strips / whatever you want to call them as you're looking at the panel ... for example slowly drag your finger nail over the surface of those film strips and look at the screen and see if there's some changes.

Then stick a little bit of foam tape on the spot, close the cover to apply just a little pressure so the cable makes contact again and cross your fingers.

[rockblues]

The chip may not be the issue.
Any of the tiny resistors and capacitors along that wide strip of circuit board can be faulty or not making a good connection to the traces on the board. On of the voltage regulators on that long board (looks like there's some on the left side in the picture but it's too low res to know for sure) could output an unstable voltage that could affect one of those ICs...

The problem may also be a poor contact between the film strips that come from the actual panel to the wide circuit board... those are almost impossible to fix by regular folks like you.
You can try to see if this is the problem by gently pressing on those strips of film / flat flex strips / whatever you want to call them as you're looking at the panel ... for example slowly drag your finger nail over the surface of those film strips and look at the screen and see if there's some changes.

You can try to see if this is the problem by gently pressing on those strips of film / flat flex strips / whatever you want to call them as you're looking at the panel ... for example slowly drag your finger nail over the surface of those film strips and look at the screen and see if there's some changes.

Then stick a little bit of foam tape on the spot, close the cover to apply just a little pressure so the cable makes contact again and cross your fingers.

Thank you!! Mariush and Terra!! Will try this!!! Bubblegum Won WWII (way before my time)!

[Rasz]

its inside the panel case, usually under a flap

Video on replacing a TCon Chip (see video): https://youtu.be/CWL0Y8g-TMo

there is no tcon chip, whole board is called Tcon. The chip being replaced in that video is a Gamma driver/buffer (AS15f). This chip going bad results in weird colors, solarized/overexposed picture etc. Definitely _not_ your problem
btw gotta love how Jimmys video doesnt show chip designation when zoomed in  fully understandable as he is trying to sell them as magic "repair kits for X". Results in people replacing random stuff in search of 'pleas bro solutions'.

TCon 01.jpg

not every black rectangle plastic thing is the same chip, now this one IS a timing controller chip
diagram of some random tcon using this one https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/TPS65150-circuit.pdf
this suggests there might be some programming involved, so straight replacement is not guaranteed to work https://wenku.baidu.com/view/9b1b9243680203d8cf2f24c3.html

How do you know if it's good or not?

finally a good question
This shows what is happening on the tcon board http://e2e.ti.com/support/power-management/f/196/p/572989/2103036#2103036


in your case defect must be in the Timing controller -> Gate driver -> glass path, resulting in correct image spread into two different vertical alignments. Can be main timing chip on tcon board, might be interconnects on the glass/gate drivers.

You can simulate your defect doing some math on a piece of paper. Flipping bits around while counting up in binary - one sticking/shorted/dead bit can result in mirror image

DELL makes PCs / Monitors by sourcing parts. The suppliers ought to be held to a high standard of quality.

DELL gives you long warranty, with cheap very quick and convenient on site support

[rockblues]

DELL makes PCs / Monitors by sourcing parts. The suppliers ought to be held to a high standard of quality.

DELL gives you long warranty, with cheap very quick and convenient on site support

- Monitor had a Dell Warranty 2016-2017. Found out if unopened, could have renewed 1 more year: 2019 - 2020
- Cost for renewing warranty = 41.00 Reinstatement Fee + 50.29 for 1 year warranty 2019-2020 = 91.94
- If something happens, you get a refurbished Monitor for 50% price of a New Monitor
- A brand new SE2717H Monitor goes for 208.00 @ B&H in NYC vs 92.00 (adding last year warranty (1 Year)) + then buying a New Monitor in 2020 for 208.00 = Total 300.00
- As Monitors seem to last at least 3 years, and maybe more, it's best to think about buying a 4 - 5 year warranty

Saying there's a cap problem with other monitors (if out of warranty), I now have the best caps from Mouser: 470uF 25v and 470uF 35v Low ESR / High Ripple Rating / High temp + boards + cables.
If I can get this TCon situation fixed, it will be a better world. Nice flow chart!!! Thanks Rasz!!

one sticking/shorted/dead bit can result in mirror image

One dead bit kills the image when Monitor is just out of warranty - planned obsolescence.

Check Dell Warranty: https://www.dell.com/support/home/us/en/04/Products/?app=warranty
Monitor Service Tag is on the lower back of the Monitor.

[Rasz]

you can risk swapping this https://www.aliexpress.com/item/32850239152.html ~$13 (ems delivery)
at least this time you will be ordering something with actual potential for success
datasheet for HIMAX chips is unobtanium, unless you live in taiwan/shenzhen and know a guy who knows a guy who drinks with a guy who works at one of the factories, there is no way of knowing if HX8861-K 73DFCG needs external programming(I dont think it does, that programming note was most likely for external serial eprom) or if its replaceable with other HX8861 variants

[rockblues]

Tried touching the cable strips - lines changed from full vertical to full horizontal - briefly clear - then black. Another one bites the dust!! Kept all parts (boards + cables) + frame - stored in the original box until the next disaster.

FWIF - B&H sells a DELL SE2719H for 199.00 - https://www.bhphotovideo.com/c/product/1374832-REG/dell_se2719h_27_16_9_ips.html 

Learned more than I knew before. Thanks everyone!!!

[Rasz]

Tried touching the cable strips - lines changed from full vertical to full horizontal - briefly clear - then black.

you mean where the strip connects to pcb? you can fix this with soldering iron
glass connection is non repairable without special bonding machines (alignment etc)

[rockblues]

you mean where the strip connects to pcb? you can fix this with soldering iron

Hi. Don't understand what strip you are referring to. Where do I solder? Still have the LCD. I was touching the eight gold strips under the panel running along the edge of the TCon Board. Do you mean where the wide cable from the main board connects to the LCD / TCon board? It seemed to snap in place ok at the TCon panel at the back of the LCD.  Amazing if this situation can be brought back to life.

glass connection is non repairable without special bonding machines (alignment etc)

Are these the 8 strips from the glass to the Tcon board? Thanks.

[Rasz]

strips are glued to the tcon pcb, glue can get weak and lose connections

you can either shim it like TERRA suggested

You can try to see if this is the problem by gently pressing on those strips of film / flat flex strips / whatever you want to call them as you're looking at the panel ... for example slowly drag your finger nail over the surface of those film strips and look at the screen and see if there's some changes.

Then stick a little bit of foam tape on the spot, close the cover to apply just a little pressure so the cable makes contact again and cross your fingers.

gently apply heat with a soldering iron/heat gun while pressing to fix broken connections
http://p1repair.com/blog/2013/05/30/lcd-repair-missing-lines/




or if experienced go for permanent solution and solder it to the tcon

[rockblues]

Wow!!! There's a reason I saved the LCD Glass. Parts are safely stored on a shelf in a box - ready to rock.

Will check out the videos and see what happens. Game is not over!!! Just like baseball.

[rockblues]

The chip may not be the issue.
Any of the tiny resistors and capacitors along that wide strip of circuit board can be faulty or not making a good connection to the traces on the board. On of the voltage regulators on that long board (looks like there's some on the left side in the picture but it's too low res to know for sure) could output an unstable voltage that could affect one of those ICs...

The problem may also be a poor contact between the film strips that come from the actual panel to the wide circuit board... those are almost impossible to fix by regular folks like you.
You can try to see if this is the problem by gently pressing on those strips of film / flat flex strips / whatever you want to call them as you're looking at the panel ... for example slowly drag your finger nail over the surface of those film strips and look at the screen and see if there's some changes.

This is a TV Repair - same idea - replacing a super small cap in the Device board that connects the glass to the TCon board

[jpanhalt]

@Rasz,

OK, I watched the second video.   Very messy and horrible music.   After that epileptic repair, did it actually work?

[Rasz]

@Rasz,

OK, I watched the second video.   Very messy and horrible music.   After that epileptic repair, did it actually work?

second video only shows that its possible to remove glue and directly solder flex to pcb

[rockblues]

second video only shows that its possible to remove glue and directly solder flex to pcb

Today - Fixed a 5.00 Multimeter (Ebay) - NEW 7 FUNCTION DIGITAL MULTIMETER DC AC MULTI-TESTER VOLTMETER OHM - loose test lead connections. To test current, I can add a 3rd removable test lead if  ever needed. Right now testing Capacitance, Voltage , Ohms, and Continuity. Cut off test leads and soldered wires directly to circuit board of the MM - Works Great!!

Testing Capacitance with Cheap 5.00 Multimeter -


Don't have a hot air gun. Plan: unglue strips by heating the strip tape carefully / quickly with a soldering iron   adding Fast Chip SMD Removal Alloy to the tape. The SMD Fast Chip Alloy lowers the boiling point of solder / it might lower the melting point of the glue. Clean residue with isopropyl alcohol. Then solder strips in. Need to also check for bad caps on the digital panel by the TCon board.

I ordered -

- Fast Chip Kit for Quik SMD Removal with a Low Temperature Alloy - SMD Removal Alloy - Ebay 
- Liquid Flux - CIRCUITWORKS CW3220 NO CLEAN SOLDERING LIQUID FLUX LEAD FREE - Ebay
- (X2) SMT SMD Component Welding Practice PCB Board Soldering Plate DIY Suite Kit - Ebay - Practice - Practice - Practice!!!!
- Fluke TL75 Hard Point Test Lead Set for Multimeter for FLUKE - Ebay
- Fluke 101 Basic Digital Multimeter Pocket Portable Meter Equipment Industrial (Amazon Good Price)

Alot of this gear I will have for many future repairs. Looking at this as an investment. And I was going to throw away the LCD Panel the other day!! Gut tells me if I can get this repair to work, it will last a long time. Plus, I'm learning alot which I really needed to do and appreciate. Must keep costs down. 

[Rasz]

instead of ripping all the strips start by touching them until you get back the picture and identifying where the defect lies

[rockblues]

instead of ripping all the strips start by touching them until you get back the picture and identifying where the defect lies

Earlier this week, I tried lightly rubbing the strips with my finger, and I found one area - right of the middle of the long thin digital board - that made the screen clear for a few seconds. Then it went back to lines. When I find it again, what do you recommend? Simply soldering with heat? Or ungluing the strip, then soldering?

Need wait for the SMD Fast Chip SMD alloy (to remove the strip) then Liquid Flux to solder.

[Rasz]

heat up with soldering iron and press with something blunt while it cools down, like in the Fluke repair video

[rockblues]

heat up with soldering iron and press with something blunt while it cools down, like in the Fluke repair video

Appreciate this. Will watch the Fluke video again right now. Thanks.

[rockblues]

- Red Meter on continuity - checked all caps on the digital strip under the flap back of panel. None were at 0. Need to know more about what I'm doing here.
- Cleaned the metal ends of both ribbon cables and the digital panel with Deoxit - let air dry.
- Connected all parts. Left the panel with flap open. Moved a QTip , then my finger over all strips before power. 
- Plugged in power. Monitor half assembled. Panel lying in the front bezel with the bracket taped in so I could raise the panel and see the screen.

With power on, checked each of the eight strips connecting LCD to circuit board. No change in screen events with finger going over each strip. Noticed New Result: One Text Box was clear!!! Second box: distorted. Not sure why there is a 2nd text box? Before I could apply heat from soldering iron, the panel went dark. Couldn't turn it on. Just to be safe, pulled the plug. Don't know what happened. Packed parts again carefully away except the panel. Attached the back flap cover. Waiting to hear what to do next.

BTW - Dell Self Test (Monitor + Power Only) used to say "No HDMI Cable" - now "No VGA Cable." No power. Black screen. No backlight. Did the monitor die? It must be the 4 min THEN Power Saving Mode!!!

There is a chance to get this working!!!!!

[rockblues]

instead of ripping all the strips start by touching them until you get back the picture and identifying where the defect lies

Today it seemed that no matter where I touched the 8 strips, it was all the same: nothing changed. What made the 1st box clear I believe was using Deoxit on the ends of both ribbon cables and also spraying the circuit boards with Deoxit as well. Air dried before applying power to test the monitor.

More about Deoxit: https://caig.com/deoxit-d-series/

[Renate]

You asked where to get the aluminum tape.
I use the stuff that they use for HVAC air ducts.
You can buy it locally anywhere.
https://www.3m.com/3M/en_US/company-us/all-3m-products/~/3M-Foil-Tape-3340/?N=5002385+3293241172&preselect=3293786499&rt=rud