LENOVO G40-45 no power

[Yosua]

hi bro I hope someone can help me on this lenovp gr0 45 nm-a281 rev 1.0 mobo, i.e. voltage loss of 3v and 5v on PL 401 and PL 402, this is BQ737 measurement when connected to charger
ACIN PIN1=18.71v
ACP PIN2=18.72v
CMPOUT PIN3=0v
CMPIN PIN4=0v
ACOK PIN5=0.36V
ACDET PIN6=2.44v
IOUT PIN7=0.3v
SDA PIN8=0v
SCL PIN9=0v
ILIM PIN10=0V
BM# PIN11= 0v
SRN PIN12=18.72V
SRP PIN13=18.71V
GRD PIN14
LODRV PIN15=0V
REGN PIN16= 0.33V
BTST PIN17=18.37
HIDRV PIN18=18.71V
PHASE PIN19=18.74V
VCC PIN20=19.10V

Thank you, I hope my colleagues can help me.

[mon2]

Re: LENOVO G40-45 no power

Post all voltage on PU401 and PU402 buck regulators.

These are intended to be always on regulators.

[lapfix]

Re: LENOVO G40-45 no power

This voltages are wrong/low..recheck your measurement
ACOK PIN5=0.36V
ACOK PIN5=0.36V
REGN PIN16= 0.33V

And post voltages of the 2 first mosfets = drain , gate and source

[mcplslg123]

Re: LENOVO G40-45 no power

His problem doesnt seems related to charging IC. 3V LDO is not generated as SDA/SCL pins are all zero. So the problem is 3V pwm regulator.

[mon2]

Re: LENOVO G40-45 no power

His problem doesnt seems related to charging IC. 3V LDO is not generated as SDA/SCL pins are all zero. So the problem is 3V pwm regulator.

Yup. OP has not replied with the requested voltage checks.

Post all voltage on PU401 and PU402 buck regulators.

These are intended to be always on regulators.