1. rblackburnuk

    OP rblackburnuk Member
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    Hoping someone here can help as I'm at a loss right now.

    I purchased a faulty unpatched switch from eBay as I'm looking to learn a bit more about 1) repairing and 2) modding. It was listed as doesn't turn on or charge and the seller stated it had never been opened. Having received the console I'm inclined to believe it had never been opened as the screw heads had no markings and the console was a bit dusty inside, plus the back cover was a bit of a pain to get off.

    The switch won't turn on, no image or charge icon on the screen.

    After taking a look I determined it is charging as the battery voltage was increasing. My USB a meter shows it was charging at 0.53a and never switched to fast charge.

    I left it overnight as I saw online if the battery is really drained it will slow charge for several hours, however, this was still the case in the morning.

    After taking it apart and removing the board (HAC-CPU-01) I couldn't find any shorts on the M92T36, the P13USB or the BQ24193. However, I noticed that the power flex cable near the connector had a hard crease in it which could be enough to prevent the power button working but I assume the charge icon would still appear. (flex cable ordered and waiting for delivery)

    I saw another thread here which said to check pins 5/6 on the M92T36. I forgot I had the charging plugged in and in doing so managed to short something resulting in the 2 of the 3 caps above M92T36 showing shorts.

    I ordered a new M92T36 and replaced this today, the shorts have gone and I'm back to how it was to start. (Phew).

    The filters near the P13USB also have continuity.

    Ok so I have a couple of weird issues that might give some insights...

    The 2 caps next to the left of the M92T36 which I believe go to pin 5/6, both show 3.90V which if I'm not mistaken is correct.

    The battery will charge to about 4.92V, if I unplug the charger, let it sit for an hour or 2 the battery will show about 4.70V and when I plug the charger back in its actually charging at a rate of 0.01v every 12-16 seconds give or take, this seems quick to me unless I'm mistaken so could this actually be fast charge even tho the USB amp meter says otherwise?

    Does this also suggest something is drawing power from the battery?

    The second issue is if I test the test point above the charge point its showing 5.80v using a Samsung USB-C charger cable. If I try the official Nintendo one (didn't come with this switch) its showing 17.61V. This charging cable is actually from a switch lite and charges this fine.

    At this point, I'm lost on what to check next, without changing chips for the sake of changing them I'm at a standstill.

    Hopefully, someone has some insights into what I can test to try and get this board working.

    Many thanks
     
    FXDX likes this.
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