2x Lenovo Ideapad 320 power problem - whole series problem

[ktmmotocross]

Hello.I have two Lenovo Ideapads 320 with the same problem.

NO voltage after first mosfet. after replace first mosfet have pulsing voltage around 3.5V after first mosfet, but still no charge or power. i replace charger ic BQ24780S but nothing changed. but when i connect GOOD battery everything works. when battery not connected or connected BAD/low voltage/ batery i have no power.

When i short first mosfet just for a while everything works even without battery until charger remove

i measured that almost everything works but have no ACDRV/pulsing to 3.5V after mosfet replace/, no ACOK without battery

pu301
pin28 vcc 19v ok
pin6 ACDET 2.8v ok
pin5 ACOK 0v ok
pin3 CMSRC 0v/pulsing to 3.5V after mosfet replace/
pin4 ACDRV 0v/pulsing to 3.5V after mosfet replace/
pin24 REGN 6v ok

i see MANY of these model with same error. have somebody some ideas?

[mon2]

Re: 2x Lenovo Ideapad 320 power problem - whole series problem

Hi.

1) can you link or post the schematic for the logic board? Have not yet checked my schematic database for the same.

2) pin #5 ACOK PIN = 0v is not OK.

3) remove all power. Meter in resistance mode. Check the resistance to ground of ACOK PIN #5.

What is the resistance and scale used on your multimeter?

[mon2]

Re: 2x Lenovo Ideapad 320 power problem - whole series problem

Ok - believe to have found the schematic.

1) Logic board block diagram references the charger IC as PU301 but the actual schematic shows as PU201. Nice.

2) Review to check which resistors are present on the ACOK signal line.

Post the location and do check the voltage on the other side of the resistor - do you have ~6v on the other side of PR214 ?

Confirm which of these 3 resistors are on your logic board.

[ktmmotocross]

Re: 2x Lenovo Ideapad 320 power problem - whole series problem

Ok - believe to have found the schematic.

1) Logic board block diagram references the charger IC as PU301 but the actual schematic shows as PU201. Nice.

2) Review to check which resistors are present on the ACOK signal line.

Post the location and do check the voltage on the other side of the resistor - do you have ~6v on the other side of PR214 ?

Confirm which of these 3 resistors are on your logic board.

only one as on schematics

[mon2]

Re: 2x Lenovo Ideapad 320 power problem - whole series problem

1) Remove all power. Meter in resistance mode.

Check the resistance of the mosfet pins @ PQ202, PQ203 (battery mosfet), PQ205 and PQ206 to confirm that they are not defective.

Multimeter in resistance mode (start with the lowest scale).

Check the resistance across the mosfet pins as follows:

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)

Post the readings for the each mosfet. Also post the scale on your meter used for the measurements.

If you see a '1' on the meter, this means the resistance is higher than the meter scale so switch to the next higher scale.

2) Confirm the presence and resistance of parts @ PR206 and PR207.

3) Confirm the soldering of the replacement charger IC is ok.

[mcplslg123]

Re: 2x Lenovo Ideapad 320 power problem - whole series problem

If evrything fails try jumpering a wire from drian of PQ311 to PR311,pin2 and see if it works. Take note that Jumper should be soldered on PR311,pin2 only. This will bypass the current sensing but on most boards this works with BQ24780S.

[ktmmotocross]

Re: 2x Lenovo Ideapad 320 power problem - whole series problem

If evrything fails try jumpering a wire from drian of PQ311 to PR311,pin2 and see if it works. Take note that Jumper should be soldered on PR311,pin2 only. This will bypass the current sensing but on most boards this works with BQ24780S.

nope still the same. work only with good battery

[ktmmotocross]

Re: 2x Lenovo Ideapad 320 power problem - whole series problem

WTF?

i see on charging ic ADP signals, but charger dont have checking for Wattage by middle pin. I have one Asus i think k54 that have same problem, but on original charger everything works. so i unplug charger cable from my PSU and attach it to lenovo charger. Connect to laptop and BAM. everything works normal. even without battery.

So how PSU make charger ic to not start, but without checking of middle pin?

[Stevedb]

Re: 2x Lenovo Ideapad 320 power problem - whole series problem

Is tha adapter with small pin connector? It has a detection to see if theis full inserted and it will not start otherwise do you have a picture of the connector.

[ktmmotocross]

Re: 2x Lenovo Ideapad 320 power problem - whole series problem

its this cable
https://www.aliexpress.com/item/1005...69e31802xYxdc3

and this PSU DPS3005
https://www.aliexpress.com/item/1005...61951546%21sea

maybe this PSU works some other way than charging IC liked

[Stevedb]

Re: 2x Lenovo Ideapad 320 power problem - whole series problem

Yea maybe i see not a charger detiction pin on this connector. Is the pin same lenght as they from original charger. I got a case where i had one if i shorted two pins on the connector board works. I do not know anymore it was acer or lenovo laptop that was the problem. Replacement adapter i got from client was a little shorter then the orinal and doesn't close adapter detection pin.

[ktmmotocross]

Re: 2x Lenovo Ideapad 320 power problem - whole series problem

i use this cable to attach to charger with cut cable. so only thing that changes is charger, not cable