Redmi note 3 not charging, the usb is dead, warning with chargers QC, possible fix.

[Frenzi2012]

I was studying this problem, people charge the phone with QC3.0 chargers and the phone stops charging, what really happens is that the zener diode that has the charging plate for security reasons (stabilizes the load voltage) Stop charging because the zener it's short-circuited (QC gives more voltage than it supports, is designed for 5v, there is QC of 12v or more). A possible solution is to cut the zener. (It works again but without voltage stabilization, it would be better to replace it but it is very complicated).
I leave some images for the one who has the problem and does not get the spare.
There is also a zener diode on the other side, on the motherboard, if cutting the zener in charge plate does not serve, check the motherboard zener.
View attachment usb.zip

 

[Frenzi2012]

deleted

 

[wwenigma]

Thanks!

 

[kaushal64]

Is this problem occur due to qc 2.0?

 

[Leo32guarulhos]

Thank you for the tip!

I was studying this problem, people charge the phone with QC3.0 chargers and the phone stops charging, what really happens is that the zener diode that has the charging plate for security reasons (stabilizes the load voltage) Stop charging because the zener it's short-circuited (QC gives more voltage than it supports, is designed for 5v, there is QC of 12v or more). A possible solution is to cut the zener. (It works again but without voltage stabilization, it would be better to replace it but it is very complicated).
I leave some images for the one who has the problem and does not get the spare.
There is also a zener diode on the other side, on the motherboard, if cutting the zener in charge plate does not serve, check the motherboard zener.
View attachment 4348127

Thank you for the tip!
To get back to life my redmi note3 ... if it were not for you XDA would have lost my device ... because here in Brazil no technician could solve this problem ... thank you and MERRY CHRISTMAS to everyone!:good:

 

[Frenzi2012]

Thank you for the tip!
To get back to life my redmi note3 ... if it were not for you XDA would have lost my device ... because here in Brazil no technician could solve this problem ... thank you and MERRY CHRISTMAS to everyone!:good:

happy that it worked, happy holidays!

 

[Frenzi2012]

Is this problem occur due to qc 2.0?

Processor support qc2.0 and 3.0 but hardware added by xiaomi not. Use 5v 2A chargers aka Qc1.0

 

[animeallen]

How do you cut the diode?

EDIT: Nevermind, I just used a needle and used it to grind the diode in half. And it worked! Thank you!

 

[Frenzi2012]

How do you cut the diode?

EDIT: Nevermind, I just used a needle and used it to grind the diode in half. And it worked! Thank you!

Perfect!

 

[Frenzi2012]

How do you cut the diode?

EDIT: Nevermind, I just used a needle and used it to grind the diode in half. And it worked! Thank you!

question, do you used a QC2.0 or QC3.0 to burn the diode?

 

[animeallen]

question, do you used a QC2.0 or QC3.0 to burn the diode?

Can't really answer that question right now since I'm not sure. It was a car charger my brother bought, it was definitely Quickcharge, just not sure which version. I'll let you know once I check.

 

[Frenzi2012]

Can't really answer that question right now since I'm not sure. It was a car charger my brother bought, it was definitely Quickcharge, just not sure which version. I'll let you know once I check.

:good:

 

[AravindhStanley]

Is there any video guide to follow to perform this. My phone is not charging too, all of a sudden.

 

[Frenzi2012]

Is there any video guide to follow to perform this. My phone is not charging too, all of a sudden.

download zip with pictures, someone commented that I cut them with a needle, maybe @animeallen can guide you...
On the other hand, did you burn it with a QC2.0 or 3.0 loader? helps us to prevent, if you can answer the poll better

 

[palbadi]

I was studying this problem, people charge the phone with QC3.0 chargers and the phone stops charging, what really happens is that the zener diode that has the charging plate for security reasons (stabilizes the load voltage) Stop charging because the zener it's short-circuited (QC gives more voltage than it supports, is designed for 5v, there is QC of 12v or more). A possible solution is to cut the zener. (It works again but without voltage stabilization, it would be better to replace it but it is very complicated).
I leave some images for the one who has the problem and does not get the spare.
There is also a zener diode on the other side, on the motherboard, if cutting the zener in charge plate does not serve, check the motherboard zener.
View attachment 4348127

Not sure but QC 3.0 charger does not charge your device at 9V or 12V until your device too has QC 3.0 qualified hardware(QC 3.0 circuit or equivalent) and software(kernel).

Cases like yours might be due to QC charger quality, which one did you use?
There are many low budget QC 3.0 chargers available like Aukey , Blitzwolf. I have Blitzwolf S9, charge my RN3 with it occasionally. And also I use MI Powerbank 2 (not 2i) for everyday charging and it is QC 3.0 input and output. Cannot check if my Zener diode is shorted but no changes in charging till now.

Charger's QC specialized circuit determine how much voltage (5v or 9v or 12v) and also current (~2A @5v or ~3A @5v or ~2A @9V etc.) should be given to device after detecting phone's charging circuit. So low budget QC 3.0 chargers may cause voltage or current rise.

And for RN3, do not set current (in any kernel) at 2.4A (it will cause damage due heat which is main culprit in long run) , 2A is sufficient but kernels with some ROMs (like NOS 8.1 for me), it charges at 1.4-1.5A. In such case, you can flash other kernels for fast (2A) charging.

My Mi Powerbank 2 charged my phone at almost (2A) in RR, Lineage 14.1 , lineage 15, pixel experience 8.1 roms.
Now in NOS 8.1 it charges at 1.4A in average.

 

[Frenzi2012]

Not sure but QC 3.0 charger does not charge your device at 9V or 12V until your device too has QC 3.0 qualified hardware(QC 3.0 circuit or equivalent) and software(kernel).

Cases like yours might be due to QC charger quality, which one did you use?
There are many low budget QC 3.0 chargers available like Aukey , Blitzwolf. I have Blitzwolf S9, charge my RN3 with it occasionally. And also I use MI Powerbank 2 (not 2i) for everyday charging and it is QC 3.0 input and output. Cannot check if my Zener diode is shorted but no changes in charging till now.

Charger's QC specialized circuit determine how much voltage (5v or 9v or 12v) and also current (~2A @5v or ~3A @5v or ~2A @9V etc.) should be given to device after detecting phone's charging circuit. So low budget QC 3.0 chargers may cause voltage or current rise.

And for RN3, do not set current (in any kernel) at 2.4A (it will cause damage due heat which is main culprit in long run) , 2A is sufficient but kernels with some ROMs (like NOS 8.1 for me), it charges at 1.4-1.5A. In such case, you can flash other kernels for fast (2A) charging.

My Mi Powerbank 2 charged my phone at almost (2A) in RR, Lineage 14.1 , lineage 15, pixel experience 8.1 roms.
Now in NOS 8.1 it charges at 1.4A in average.

For me the chargers detect the snapdragon 650 and send more power, the zener diode must support 10w only( i think no found info), I have comments above saying that they were burned with chargers QC, I'm trying to determine if qc 3.0 or 2.0

Enviado desde mi Redmi Note 3 mediante Tapatalk

 

[Frenzi2012]

Not sure but QC 3.0 charger does not charge your device at 9V or 12V until your device too has QC 3.0 qualified hardware(QC 3.0 circuit or equivalent) and software(kernel).

Cases like yours might be due to QC charger quality, which one did you use?
There are many low budget QC 3.0 chargers available like Aukey , Blitzwolf. I have Blitzwolf S9, charge my RN3 with it occasionally. And also I use MI Powerbank 2 (not 2i) for everyday charging and it is QC 3.0 input and output. Cannot check if my Zener diode is shorted but no changes in charging till now.

Charger's QC specialized circuit determine how much voltage (5v or 9v or 12v) and also current (~2A @5v or ~3A @5v or ~2A @9V etc.) should be given to device after detecting phone's charging circuit. So low budget QC 3.0 chargers may cause voltage or current rise.

And for RN3, do not set current (in any kernel) at 2.4A (it will cause damage due heat which is main culprit in long run) , 2A is sufficient but kernels with some ROMs (like NOS 8.1 for me), it charges at 1.4-1.5A. In such case, you can flash other kernels for fast (2A) charging.

My Mi Powerbank 2 charged my phone at almost (2A) in RR, Lineage 14.1 , lineage 15, pixel experience 8.1 roms.
Now in NOS 8.1 it charges at 1.4A in average.

i using NOS 8.1 with stock kernel and original MI charger 2A 5V, charging speed 1998mA from 10% to 50 % then slowdown to 1600mA aprox and 90 to 100% 600mA aprox

 

[nguyenlucky]

I activated 2.4A option in whatever kernel I used, but I dont rely on it too much.
Primary charger is HTC 1A, only use my Aukey QC2.0 when I need quick refuel. And my phone still rock stable though

 

[otyg]

Never burned mine out but I have a QC 3.0 charger and when I plug it to the phone it charges at the normal rate of 5v 2A, so I rarely use the QC port on the charger since it's the same as using the stock charger or normal ports, my guess is there are many custom kernels causing this damage, and I think there was one rare miui beta that enabled it at one time, I'm not sure if there is fake QC chargers but I believe real / official ones the circuitry is made by qualcomm and it does a series of checks to see if the device can support it or not-which it never did activate on my QC charger at least (I have a Choetech QC charger that cost around $30), which was pretty costly considering I never got to use the QC feature, but I think it's well built and never gives problems so in a way it was worth it and it's available if I get a device with proper QC support.

https://www.choetech.com/product/usb-charging-station-with-2-quick-charge-3.0-6port-us.html

 

[psndna88]

Never burned mine out but I have a QC 3.0 charger and when I plug it to the phone it charges at the normal rate of 5v 2A, so I rarely use the QC port on the charger since it's the same as using the stock charger or normal ports, my guess is there are many custom kernels causing this damage, and I think there was one rare miui beta that enabled it at one time, I'm not sure if there is fake QC chargers but I believe real / official ones the circuitry is made by qualcomm and it does a series of checks to see if the device can support it or not-which it never did activate on my QC charger at least (I have a Choetech QC charger that cost around $30), which was pretty costly considering I never got to use the QC feature, but I think it's well built and never gives problems so in a way it was worth it and it's available if I get a device with proper QC support.

https://www.choetech.com/product/usb-charging-station-with-2-quick-charge-3.0-6port-us.html

kernel can allow charger to pump in high current
many users have faced this
some carelessly do it knowingly

hence, AGNi limits it at max 2100mA no matter how badly users want to use QC currents.

Sent from my Xiaomi Redmi Note 3 using XDA Labs