No touch, LCD jumps/glitches, insert a cartridge and error code

I got this off a less than honest seller on Ebay. It was claimed no parts were harvested however I found the resistors for the power button missing and a big nasty blob of solder where they should be. Broken rails and a messy SD unit had been swapped into this machine… It was a mess.

First thing I noticed was the LCD malfunctioning and the touch panel would not function. It works perfect in docked mode. Some obvious work had been done in the area with the power and fan connections on MB. I replaced the resistors (missing) for the power button and reflowed the port so now volume +/- also work. The connector on the MB to the cartridge slot looks… iffy. I think someone tried to replace it but all the components surrounding are at least on the board. It is exploitable and I can send payloads. I sent it biskey reading that if the graphic glitches disappear with it, likely software/battery reset issue. Same unusual glitching/tearing/blinking. Definitely thinking hardware at this point.

I put the MB in another Switch and got exactly the same symptoms. I tried to put in a cartridge and get an immediate error code as if its shorting and switch asks for power off.

I dont see the back light blinking in and out under the MB when on. The ribbon connector for LCD on MB looks clean and no parts seem to be missing.

“I’d check the 8316 IC is being told to turn on the outputs and if yes if the outputs are at the correct voltage, that being +5V and -5V”

I did this and outputs are high and correct voltage. I know I need to dig deeper and measure power and resistance, but these symptoms have to point to an area I should focus on?

Buck converters?
Power Chip?
USB CHIP?
LCD IC?

I think Im going to take the MB cartridge port off (get another) to least see if that alleviates some of the weirdness. I mean its useless as it ATM.

Thank you for reading and any ideas are helpful.

Agreed that finding a different game-cart board would be a good start for the touch and error code issue. That said if the port it connects too looks bad, it could be that also… Weird LCD stuff I’m not sure.

Same behavior with two different cartridge modules One is known working.

No touch no matter what, two different screens and digitizers, one known working.

LCD glitches/phases with or without cartridge unit installed (I noticed once, and only once the screen actually behaved until next reboot). I should push on LCD IC see if its a broken ball underneath. This is what is pointing me to a short or part not making contact on the cart connector on PCB. This is why I want it off but not until I get a few more opinions.

I read this

“The touchscreen is handled by the small daughterboard which also contains the game cart slot and the audio jack socket.”

Took a closer look at the MB cart connector. Its missing 20 or so pins. So ordering a replacement and off it goes.

This explains touch panel and cartridge error. Now just that LCD. I really am starting to wonder if its caused by this “work” on the connector. Could be shorting underneath.

I would guess so, maybe one of the pins isn’t making a good connection somewhere.

I will report back after I get this part in and swap it out.

I had a similar issue with cartridge slot not working.

You may find that the donor (known working one) came from a Switch with a newer firmware. If this is the case you will need to update the firmware of the patient Switch. I had the same issue and discovered that the cartridge slot has its own fuses which burn on updates. A mismatch causes the Switch to throw an error when a game cart is inserted.

Also check there is nothing (tiny bits) in the socket on the motherboard. connecting that socket from the cartridge game slot to the motherboard can be a pain and sometimes the pins can bend inside the cartridge slot side of the connector.

Good luck.

0xCE

That is interesting information. Right now its def the missing pins in the connector, however this might come into play so I appreciate it.

This job just keeps getting more interesting. I got the connector off clean but somehow of said missing pins… The repair attempt before me removed two pads on the MB top row(the pins were just gone on these so I know I didn’t do the damage. Nothing was there to pull the pad off.(look at how bad the solder looks at those resistors, they check out but, yikes, Im looking at you simplecellllc).

Anywho does anyone have a link to the what all the lines are on MB cart connector. I’m pretty sure I can fix it. May need an alternate point.

New connector showed up in mail today!

I have been fixing other Switches as this one is being worked on.

Im seeing corrosion in really odd places causing shorts. No way a liquid bath caused them, there is nothing around them and just 2 or 3 random spots like the fan connector and Cartridge port pins. I cant say I’ve seen a lot of this kind of thing before. Not over multiple devices with no signs of liquid damage.

Perhaps too much flux left over from production. My climate is stupid dry. No way we should be seeing this on electronics

Keep us informed of your progress when the new connector arrives.

There is a chance the pads were NC, those are usually the ones to go first as there is no where for the heat to go. I can’t quite make out in the photo but if you see a trace leading to the pads you can just scrape at it and solder a wire.

As for corrosion that would only appear quickly where the liquid settles and there is voltage & ground exposed, flux wouldn’t be the cause of green/blue corrosion. water usually doesn’t leave much trace after it dries. The damage can be quite isolated at times.

Interesting.

I mean makes sense with kids and portable electronics… I saw it in 5 different places on two consoles that were not this one in a 3 day period. One was cart reader broken (corrosion shorted two of the cart pins, that was an easy one) the other was SD read failure due to pin failure on MB connector. This one had it on the bottom of audio jack. Could have been the initial problem on this one made much worse.

Anywho, new connector is here. I was thinking the same thing as you to get at the traces and scrape a bit I’m no stranger to the technique. I noticed after scraping a bit in the area the traces started looking copper color. I think this was attempted reflow and the solder never quite it that liquified was left on, hard but not melted. It cleaned up perfectly after pretty thorough scraping with xacto

I need a few days away from tiny electronic work, I’ve been very busy with many things, but will get back after port is installed. My eyes are bugging out from using magnifiers all week.

I am happy to report that removing the cartridge MB connector stopped all the odd screen behavior. I had to test it I couldn’t wait. I still need to put new one on but this is huge. The messy work on the port caused some sort of short to the LCD. No more tearing/jumping/blinking.

I lied. I’m a liar.

It did behave for about a half hour (seems to do this from time to time. Now back to same old screen issues.

Thats a shame. Are you able to get a photo of the screen glitching?

Putting new cart port on today. I will get a video of the glitching. Something seems a bit different now.

The LCD will behave sometimes. This was not occurring before.

Google “Full Circle Embedded” on youtube to see. It is the only video I have posted.

That was a particularly bad session. It usually does not blink back light in and out.

I cant really post pictures, its fast and random. You would have to see video I referred to above.

I was practicing on another MB before I put the new cart port on so I have yet to do that.

Figured I would try the run the battery out and recharge but it didnt help the situation. What was interesting is it seemed to “warm up” and stop accting out. I played it for 3 hours on LCD with no glitching unless it went low power or sleep and it would only do it for a few seconds on wake.

Sometimes it works. Gotta be LCD IC or backlight area methinks. I need to put some lines on the LCD IC power and 1.8v feeding it to see if they are erratic.