Hardware Fixing a water damaged switch. No video on LCD, but video in dock mode on TV.

[bevis]

Hey guys, I have a spare switch that was dropped in water. I took out the motherboard and cleaned it with 91% alcohol. And all connectors and ribbon cables were cleaned as well. When I plug it in it recieves 0.39-0.4 amps @ 5 volts but never goes into fast charging. The battery tests good and does charge, the capacitors by the charging IC and video IC were checked, no shorts. Although one capacitor had no resistance on one side and very little resistance, but not quite pure continuity on the other side. Is that as good as a short? I don't think it's shorted because it does charge, and video is being processed and put out on the TV in docking mode. But I don't get video on the LCD screen.

I took the water damaged motherboard out again and installed it in a known working switch and I'm not getting video on the LCD screen on that one either. But I am getting it out on the TV. That means the video IC is good, correct?

Any ideas?

 

[alexenochs]

water damage can do a lot to a motherboard of any console luckily we have 2 different video output methods ..a lot of things could be wrong with this console =P no clue what the issue would be cuz..water damage is a bitch ..anything could be the issue pictures would help but also..if u plan to sell this..as is please let me know your price lol

--------------------- MERGED ---------------------------

water damage can do a lot to a motherboard of any console luckily we have 2 different video output methods ..a lot of things could be wrong with this console =P no clue what the issue would be cuz..water damage is a bitch ..anything could be the issue pictures would help but also..if u plan to sell this..as is please let me know your price lol

also to mention I don't know the issue just know someone who just got a lite...that would love to have a way to play on the tv

 

[bevis]

Thanks for the offer, right now I'm interested in figuring this thing out. I got excited because one of the pins on the connector for the back light looked brown, so I cleaned it, however the ribbon connector for the back light only has 4 connection pads that face down. The pin I cleaned wasn't effected. Touch screen capabilities do work, however I think this touch screen is toast. I can't post any pictures yet because I'm new. Maybe I'll shitpost in the free talk section for a bit.

All the pins for the LCD connector look nice and clean. Straight and make good contact I believe. Is there a service manual for these things floating around somewhere maybe?

 

[bootaholic]

Check the pads on the backlight connector. Very common for the right most one to corrode and fall off when liquid damaged. Likely the LCD is actually on but the backlight is not.

Sent from my Pixel 2 using Tapatalk

 

[Agilato]

Can we see actual pictures of the board?
I usually prefere to start with ultrasonic cleaner(saves my time a lot).
Some ppl fix problem first and then use ultrasonic cleaner, but i like to go opposite.
Also get yourself 99% IPA, 91% quiet useless for PCB cleaning.

 

[bevis]

I wish I still had an ultrasonic cleaner. And you're right, the alcohol leaves a noticeable residue. Hopefully I can upload some pictures soon. I'm 3d printing a camera mount for my microscope.

 

[bevis]

Check the pads on the backlight connector. Very common for the right most one to corrode and fall off when liquid damaged. Likely the LCD is actually on but the backlight is not.

Sent from my Pixel 2 using Tapatalk

The LCD, backlight and touchscreen all work with a different motherboard. I've now got the water damaged switch booting up, accepting both controllers, making sounds, the touch screen works, docked video works but no LCD image or backlight. I tried shinning a light in to see if the LCD is running without the backlight, but I see nothing.

 

[bootaholic]

The LCD, backlight and touchscreen all work with a different motherboard. I've now got the water damaged switch booting up, accepting both controllers, making sounds, the touch screen works, docked video works but no LCD image or backlight. I tried shinning a light in to see if the LCD is running without the backlight, but I see nothing.

Any bent pins in the LCD connector? Corrosion in the pins of LCD / backlight connector?

Sent from my Pixel 2 using Tapatalk

 

[bevis]

Check the pads on the backlight connector. Very common for the right most one to corrode and fall off when liquid damaged. Likely the LCD is actually on but the backlight is not.

Sent from my Pixel 2 using Tapatalk

Any bent pins in the LCD connector? Corrosion in the pins of LCD / backlight connector?

Sent from my Pixel 2 using Tapatalk

I just shined a really bright flashlight into it while in a dark room and yes, the LCD is working. It's a backlight issue. When I first opened the case the pin to the left of this blue arrow was dark orange. I carefully took a needle and some deoxit and scraped it as clean as I could. The pads on the ribbon cable face down however so it seems this corroded pin really only caused tension up against the already clean pins.

Do you think its just a dirty pin?

 

[bootaholic]

I just shined a really bright flashlight into it while in a dark room and yes, the LCD is working. It's a backlight issue. When I first opened the case the pin to the left of this blue arrow was dark orange. I carefully took a needle and some deoxit and scraped it as clean as I could. The pads on the ribbon cable face down however so it seems this corroded pin really only caused tension up against the already clean pins.

Do you think its just a dirty pin?

It's possible the pin on the bottom side is corroded but it's also possible one of the corroded circuits broke. Check each of the pins going to the backlight connector to see if you're getting power. If you have a SMD heat gun you can remove the backlight connector and replace, if needed.

I don't see a picture by the way.

Sent from my Pixel 2 using Tapatalk

 

[Agilato]

Sometimes corrosion can get under the pin soldering join you have to test with needle under the microscope or magnification if all pins are sitting well.
Short in backlight circuit also might cost some issues.
It's had to tell mb you missing something obvious, we need pictures.

 

[bevis]

The black locking latch on the back light connector feels loose and shitty. Looks like I'll be ordering a new one. I did test voltage and I got 4 volts on the pin that has the brown corrosion on it. Both on the pad that is soldered to the board and the pin inside the connector that makes contact with the ribbon. I also tried applying pressure with the switch on to see if contact could be made, but the screen never lit up. Here are some pictures.

 

[Agilato]

Doesn't look bad at all, mb you have corrosion under pin, open latch and see if at least all pins under it are soldered, you problem might be very easy to fix.
Looks too shiny for IPA cleaned board... your IPA is really bad or it's just flux?

 

[bevis]

I put deoxit on it to try and break up current and prevent future corrosion.

 

[Agilato]

I put deoxit on it to try and break up current and prevent future corrosion.

Is this product aren't conductive?

 

[bevis]

Is this product aren't conductive?

It's this https://www.amazon.com/CAIG-LABORAT...ocphy=9028692&hvtargid=pla-349776659890&psc=1

I went ahead and touched each of the 4 pins with a hot iron to reflow the solder incase there was a bad connection or something. Still no backlight. The ribbon is in there pretty tight even though the latch feels a bit weak. I don't get it. The 4 pin connector is geting 4 volts to it, the ribbon is clean and in there snug, the backlight worked with another motherboard. What else is there to test?

 

[bootaholic]

It's this https://www.amazon.com/CAIG-LABORAT...ocphy=9028692&hvtargid=pla-349776659890&psc=1

I went ahead and touched each of the 4 pins with a hot iron to reflow the solder incase there was a bad connection or something. Still no backlight. The ribbon is in there pretty tight even though the latch feels a bit weak. I don't get it. The 4 pin connector is geting 4 volts to it, the ribbon is clean and in there snug, the backlight worked with another motherboard. What else is there to test?

Use the other board as a reference, probe between the two to see if there's any inconsistencies. Ground circuit might have issues.

Sent from my Pixel 2 using Tapatalk

 

[Agilato]

It's this https://www.amazon.com/CAIG-LABORAT...ocphy=9028692&hvtargid=pla-349776659890&psc=1

I went ahead and touched each of the 4 pins with a hot iron to reflow the solder incase there was a bad connection or something. Still no backlight. The ribbon is in there pretty tight even though the latch feels a bit weak. I don't get it. The 4 pin connector is geting 4 volts to it, the ribbon is clean and in there snug, the backlight worked with another motherboard. What else is there to test?

It's tight because some flux after soldering and solution you put in. Kind of ok. But i would work it out with IPA

 

[bevis]

Quick update. I picked up an ultrasonic cleaner from harbor freight. Cleaned the board with an 80% distilled water 20% 91% isp alcohol mixture for 8 minutes with heater on. Pulled the board out, sprayed it with alcohol and brushed it. Blasted with conpressed air and let it sit until it was bone dry. I put it back in and still no backlight. The sound and digitizer were working however, but after around the 3rd or 4th time of rebooting it the sound stopped. It still docks onto the TV just fine, but no sound. Any ideas?

Scratch that, audio is now working, but touch screen is not. I've looked all all connectors through a microscope and they're all clean, no bent pins. Going to let this sit unplugged for the night and see what that do.

 

[andres1234]

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