[Solved] JBL Flip 3 - Won't turn on or charge, no response please help.

Hello.
I bought a jbl flip 3 speaker that would not turn on.
Initially, I thought that the problem was with the battery or the micro usb socket, but both of these parts turned out to be working.
In the loudspeaker you can see that someone has been transferring the battery connector.
Holding the power switch for 30 seconds does not give anything, nor does connecting the charger.
When you click the power button, the lights around it will only flash and that's it.
Below are the voltage measurements.
On the power switch before switching on 4.05 v, after pressing 0 v.
The battery is 4.17v - regardless of the button combination, the voltage does not drop.
Tensions on the board:
vcc to gnd 3.283 v
csb to gnd 3.278 v
miso, clk, mos 0v
vcc for mos, clk, miso 3.118 v
All these voltages are available after pressing the power button, without pressing the voltages.

I am asking for help in finding the fault and where to look for it, best regards.
Photos in the attachment because normally would not stick.
https://filmy.elektroda.pl/83_1526068234.mp4

kacperos9371 wrote:

I am asking for help in finding the fault and where to look for it, best regards.

Check if the 10V converter is functional, if there is no this voltage, the terminal may be damaged and it causes the converter not to start, or the converter itself is damaged.
This device is so complicated that the possibilities and reasons for its inoperability are "thumping", and the measurements and SM should make it easier to find the damage.

On the U7 MP9428 chip, pin 3 is 3.85 V.
On the Q1 MTB04N03 chip, pins 5, 6, 7, 8 are 3.78 V, pins 1, 2, 3 are 4.18 V, and pin 4 is 4.07 V.

kacperos9371 wrote:

On the Q1 MTB04N03 chip, pins 5, 6, 7, 8 are 3.78 V, pins 1, 2, 3 are 4.18 V, and pin 4 is 4.07 V.

And for pin 1,2 Q2?

Q2 on pins 1 and 2 no voltage.
In addition, I found one, probably a capacitor, missing on the U1 board. It may be preventing you from turning on.

kacperos9371 wrote:

Q2 on pins 1 and 2 no voltage.

Did you measure to weight?
Measure on the basis of Q3.
What is R 505 combined with?

kacperos9371 wrote:

In addition, I found one, probably a capacitor, missing on the U1 board.

Give its designation from the diagram, because from this photo it is impossible to determine which capacitor it is.

This is how I measured pin 1, 2 to ground and it was about 8 mV on pin 3 3.7 V
Today I measured pin 1, 2 a second time and, surprisingly, it is 423 mV on pin 3, then 3.7 V. Earlier I measured it well so I do not know where this voltage is suddenly. Pin 1, 2 of Q2 to Q3 3.3V base.
R 505 connects to pin 27 (Deep_Sleep) on the U1 chip.
Unfortunately, as for the capacitor on the board, there are no markings in the diagram, only the entire U1 circuit is marked

kacperos9371 wrote:

Unfortunately, as for the capacitor on the board, there are no markings in the diagram, only the entire U1 circuit is marked

Which pin U1 is this capacitor connected to?
Check if there is anything sticking to the ground on the 10V line.
In the "diode" range of the meter, measure, the red probe to pin 1 or 2 of Q2, and the black probe to ground, just disconnect the power supply before measuring.

The broken capacitor on U1 is connected with one pad to pin 46 and 47 and the other goes to the bga circuit.
I do not see short circuits on the 10 V line.
Black ground / red pin 1 value increases to 3 volts then the meter displays .OL
The red ground / black pin 1 is 0.5 V. All tests without batteries.
Q2 pin 1 to plus bat 4.3v
Q2 pin 1 to whip ground from 8-500 mV.

kacperos9371 wrote:

The broken capacitor on U1 is connected with one pad to pin 46 and 47 and the other goes to the bga circuit.

According to the diagram, it does not connect to pin 46, but to pin 47 C107 100nF.
It looks like something with the U1 is wrong, damaged, or there is no power.

After applying the meter to the capacitor pad, it squeaks at pins 46 and 47 U1

kacperos9371 wrote:

After applying the meter to the capacitor pad, it squeaks at pins 46 and 47 U1

I don't know if it should be connected or not, no board drawing, give me a picture.

Maybe mark these points.

[img-0]

This capacitor on pin 46 is not to be and is not there, and it is on pin 47, which is good.

kacperos9371 wrote:

After applying the meter to the capacitor pad, it squeaks at pins 46 and 47 U1

I don't know how you measured it, but if there is a short circuit between pin 46 and 47, the system is damaged.

Now what can you do if it is damaged?

kacperos9371 wrote:

Now what can you do if it is damaged?

I do not know.
I see such a system for the first time, both in the diagram and in the photo, I was looking for some information about it, but I didn't find anything, maybe I'm looking for it wrong.
Ask in the services, maybe they will fix it.

https://pl.aliexpress.com/item/BTA-RX-SPDIF-C...eceive-module-module-aptx-ll/32817066513.html

this broken "capacitor" is actually a coil on the power line of the CSR8670 chip

If there is no short to ground on both pads of this coil, it is enough to make a jumper in this place If there is a short circuit on one of these pads, the module should be replaced


edit

pins 46 and 47 are connected to each other via r185 having a value of 0 ohms

there should be 1.8V to ground

Thank you very much to Mr. Qudlatyy for your help.
After making the bridge, the loudspeaker turns on at this point!
There is only one little problem. The loudspeaker only works when I hold power, it turns off immediately after releasing it.

Edit: The problem with switching off, however, may be related to a bad contact in the place of the bridge.
What coil should be soldered there? About what parameters?

Added after 46 [minutes]:

And one more question, solder it with a station or a hotair?

kacperos9371 wrote:

After making the bridge, the loudspeaker turns on at this point!

So the diagram has nothing to do with what is on the board.
L105 is the black element that connects to the jumper you soldered and there was probably a jumper (zero resistance) there, which is the power circuit.
What is the voltage on this armature?

kacperos9371 wrote:

The loudspeaker only works when I hold power, it turns off immediately after releasing it.

Because there is probably another damage and the protection turns off the device so that there is no more damage and that is why the jumper has been removed by someone.

3.3V power flows through the L105 to pin 45 and 48. On pin 47 there is 1.8V coming from the U1 chip, which through the R185 resistor goes to the leg 46 It is used to power the memory MX25U3235

kacperos9371 wrote:

And one more question, solder it with a station or hotair?

make a jumper in the place of the missing element, there can be a wire, solder the station with a thin tip

What is the voltage on pin 5 of the U5 chip with the power button pressed and the power button released?

With the power button released, the voltage is 0 V.
While pressed 3.3V.

If I understand correctly it should be like this:
With the button pressed, VCC_switch_3V3 appears and the system starts
at this point, R434 should show a high state, i.e. I assume 3.3V which causes Q7 conduction and thus maintains a low state (zero V) on pin 1 of Q5
Zero V on pin 1 of Q5 keeps it conductive and everything works

Please check the voltage on the R434 when you turn on the power button

Qudlatyy wrote:

3.3V power supply for pins 45 and 48 flows through the L105.

Yes, in the diagram, and on the board, which pins are they?

On the board as in the diagram

Please check the voltage on the R434 when you turn on the power [/ quote] button

3.14 V on the left and 13 mV on the right.

Check the R434 value should be around 47kOhm, you can measure without desoldering
If ok then measure the voltage on R438, R439, R440.

The R 434 has 46.89 KOhm OR OK.
R 439 bottom 3.2 V, top 0.7 V, R 438 bottom 0.6 V, top 0.5 V, R 440 bottom and top 0.7 V.

Do you have a PCB connected with the vol + and vol- keys?