820-3115-B PP5V_S3 @2.0V

[2click]

Im having trouble with this board on pp5v_s3, when I inject voltage U7200 gets hot, I already replaced U7200 with no change.

PPBUS_G3H = 12.60
PP3V42 = 3.42V
PP3V3_S5 = 3.3V
PP5V_S5 = 4.9V
PP3V3_S3 = 3.3V
PP3V3_S0 = 3.29V
PP5V_S3 = 2.0V
pp5v_s0 = 0v
P5VS3_EN_L = 0v (pulses 3.3V when I turn on the PSU, then drops)
P3V3S5_EN_L = 0v (pulses 3.3V when I turn on the PSU, then drops)
PM_SLP_S4_L = 3.3V

U7941
PIN 1 = 3,42
PIN 2 = 3,42
PIN 3 = 3,42
PIN 4 = 0V
PIN 5 = GND
PIN 6 = 3,3
PIN 7 = 0V
PIN 8 = 3,46

 

[Gurmon]

Did you replace Q7260 & Q7261 when you swapped U7200 ?

 

[2click]

No I didn´t...

 

[Gurmon]

swap out the FETS, report back...swap out u7200 same time from another donor.

 

[2click]

Just did that, still not getting PP5V_S3 ... but now it is 0v instead of 2.0v which is maybe a good sign?

P5VS3_EN_L = 0v (pulses 3.3V when I turn on the PSU, then drops, when I turn off the PSU it goes high again and drops...)

 

[Gurmon]

do you get any pulses on L7260 now that you have changed the FETS ? I wouldn't have expected you now have 0V there now?

Diode mode reading on L7260 ?

 

[2informaticos]

Post diode mode to ground at L7260.
Allow 10s after power is removed; before measuring in diode mode.

"P5VS3_EN_L"
Ends with "_L" for some reason; 0V is correct value.

Post voltage for pin 1 of U7200.
Check/replace R/C7260.

 

[2click]

L7260 = .247

"P5VS3_EN_L"
Ends with "_L" for some reason; 0V is correct value. ----> So on the entrip1 and entrip2 of U7200 I will get 0V correct?

PIN 1 U7200 = 0V
Replaced R/C7260, still not getting further...

 

[2informaticos]

"So on the entrip1 and entrip2 of U7200 I will get 0V correct?"
Why 0V?
Read datasheet.

Looks like bad U7200; pin 1 should have 1.15V.
Remove Q7221 first, just in case.

 

[2click]

Replaced U7200
PIN 1 = 1.22v
replaced Q7221, still getting 2v at PP5V_S3

 

[2informaticos]

Pin 1 is good now.
Replace Q7260/61 and R/C7260.
Be sure all traces/solders and surrounding components are good.

 

[2click]

Still the same, I replaced Q7260/61 and R/C7260 still getting 2v at PP5V_S3
is it worth removing U7200 and injecting voltage on PP5V_s3 line?

 

[2informaticos]

Why, if there is no short???

Check R7267/68 values.
Play with RA/RB untill get correct output voltage.

 

[2click]

CHANGED R7267/68 and now it is working apparently fine... thank you!!

 

[2click]

So this board turned on fine, but I am having a trouble with the Audio, the icon is there, I can adjust the volume up and down, but I can´t get any sound come out of the speakers... no even using headphones... I´ve checked U6200/01 so far and everything seems to be ok... what can cause that?

 

[2informaticos]

Any red light visible inside audio connector?
Try removing R6805.

 

[2click]

Hi, no red light on the audio jack, the volume bar works, the output says: "internal speakers" but I get no audio out from the speakers.
I connected some headphones in the jack and the output is still in "internal speakers" and doesn´t change to headphones like it usually does...

 

[2informaticos]

Looks like there is a problem with audio connector, if remains stuck on internal speakers.
Check all traces, small coils and resistors in series with the connector.
Also check U6200 output voltage.

 

[2click]

changed u6610/20 and now sound is working fine... thank you!