820-2936 water damaged, battery not detected

[Dewanbd]

It was water damaged. closed to ISL, changed it and worked fine except battery not detected. Found
R5280=3.4V both side, R5281=3.4v both side. Checked BIL looks good. Any help please.

 

[2informaticos]

Check traces and solders for pins 10/11 of ISL6259.
Post resistance to ground at SCL/SDA lines of battery bus.
Also post exact voltage for PPBUS_G3H.

 

[Dewanbd]

traces and solders for pins 10/11 of ISL6259. looks good.
resistance to ground at SCL=.455 and sdl=.456
exact voltage for PPBUS_G3H=12.4 v .Thanks.

 

[2informaticos]

Bad SMC, or battery in this case.
I would test a known good battery first.
Also recommend you try another ISL6259.
Last solution, change the SMC...

 

[Dewanbd]

Try another ISL6259 and now see no green light

 

[2informaticos]

Bad solders I suppose.
Post again the values mentioned before.

 

[Dewanbd]

PPBUS_G3H=.0.5v
resistance to ground at SCL=.462 and sdl=.461

 

[2informaticos]

"pin12=1.1v"
Bad value for 3V42.
Post voltages for U6990.

 

[Dewanbd]

Volteges for U6990:
PIN9 P3V42G3H=1.1V
PIN8 P3V42G3H_FB= 4.9V
PIN7 PPVIN_G3H_P3V42G3H=16.6V
PIN6 P3V42G3H_SW=1.1V
PIN4 PPVIN_G3H_P3V42G3H=16.6V
PIN3 P3V42G3H_TON=11/12 NOT STABLE
PIN2 P3V42G3H_FB=4.9V

 

[2informaticos]

Check resistance to ground (diode mode) at L6995.
If good, check C6991/96 and R6995.
If all good, change U6990.
Be sure all traces and solders are OK.

 

[Dewanbd]

Changed U6990 and now see the green light and battery also detected , all tested passed. Thanks for your help.