After opening a topic in the wrong section (sorry), I come back here to find a solution for the Switch Lite that worries me:
No charging, no starting. I changed the M92, BQ and charging port without success.
I just found a shorted capacitor above the BQ. I removed the latter and it turns out that it is still present on the motherboard. So I removed the top diode and it seems to be the culprit.
The problem is that I can’t find an equivalent diode anywhere…
Do you know the value or type of diode that is here? I’m looking to replace it to test.
Thanks very much !
This diode is an additional part and not needed for a propper working bq ic.
Does the coil have continuity?
Yes, the coil have continuity.
I, who thought I had found it, missed it!
Here is picture with what i find shorted / strange. Thank you
If the strange values left under the max ic where the only ones, I would desolder the en ic and check if the short is gone. Doe to low resistance to ground on the right of the max, I guess there is a problem with the SoC itself. But how knows.
I just did a new test:
I reassembled the diode I previously suspected, changed the BQ and M92 again.
So I connected the battery and there, the coil became hot, the BQ too… I have 0.08A of consumption, nothing more.
I admit I don’t really understand anymore… I also have 3 capacitors which seem to be short-circuited next to the M92.
The cap on the right of the m92t36 is the VDDIO line and it is the same at the max ic. You changed the m92t36, bq24193 so the cause should be somewhere else. I would pull the en ic and check if the short is gone.
Did you check the diode before soldering back?
I tested the diode but I’m not sure what it’s supposed to give. I have in one direction a “high” value of which I forgot the accuracy and in the other direction, a low value (0.28). I don’t know if this is normal, it seemed to me that the diode should only pass current in one direction, correct?
The coil becomes hot only when the battery is connected. I still have a doubt about the BQ component… I didn’t have this problem before the change.
I no longer know where to look. I will desolder the MAX if ever but since I have nothing to reball this component, I will perhaps wait to buy another already balled.
Correct. The diode should only pass in one direction. For testing I would take the diode out.
An other thing, if you have a short at the coil, the whole SYS line is short. That could explain why the readings right of the max ic are low.
Did you check the lines SYS and SW while bq was out?
Not at all. Can you help me for understand how i have to test it please? Thank you
The thing is to narrow things down to the cause of the short. You found a short at the bq at its SW line, so SYS is short too, due to the connection via the coil. Now the short can be at the bq or at the SYS line. If bq is out and the short is gone, the cause is on the bq side. If the short is present without the bq ic, the whole SYS is shorted.
Ok i just check it and even if i remove BQ, short still present.
If i follow your idea, that should say that the whole SYS is shorted ?
I don’t really have an idea to look for where this problem would come from suddenly… Do you have a track or a diagram concerning this line by chance?
In principle, do you know the value of the diode which is visibly burned? I search but find nothing. The 8C marking does nothing…
Can I replace it with one present on a classic Switch card by chance?
Thanks very much !
I dont think it exists on a normal switch, you should be able to get the console working without it being fitted at all. I would just remove it and go from there.
I received a donor motherboard to replace this damn diode, I did it but the short circuit remains…
Do you have an idea, a line of research to find the solution by chance?
Thanks very much !
I tried to find where my problem comes from but nothing to do…
If I remove the diode, the short circuit is no longer present but it does not light up and does not charge anyway.
So I looked on the other side and I also necessarily have a shorted capacitor. I removed it and it’s still on the card.
I confess to being totally lost and I really need a hand please.