acer v3-372 dead after battery disconnected

[dellxps15]

hi, i had a acer aspire v3-372 with 2 keyboard key not working, so i disassembled partially the notebook, disconnected the battery, removed the keyboard connector, opened the 2 key and cleaned them with compressed air and after see all looked cleaned, i power on pc with ac in and all keyboard was working. after that, i reconnected the battery, but with battery only laptop was like dead. after some battery reset botton, wait some minuted-hours nothing changed. i suspected something wrong with battery and after ordered another one problem is the same.....

that notebook should have some protection circuit and without reset it battery wont give any voltage from red wires.

anyone know what to do or where to look at ? that acer laptops have always strange working method compared to other brands.....

[SMDFlea]

Re: acer v3-372 dead after battery disconnected

Take a look at SW3 Battery Insert,it should be pressed in when the laptop is assembled.

[dellxps15]

Re: acer v3-372 dead after battery disconnected

it's 2.48 volt :| downloaded your schematic today, but yesterday i pressed both battery reset and both battery insert but nothing hapened. before doing anything i had that battery pin voltage with psu connected:

pin 1-2 0 volt
pin 3: 2.48 volt

all other pin 0 volt

then i opened the battery but 2 component (i think temperature cid were not communicating) so i soldered one wire, but today i tryed and now:

with battery and psu voltages on battery connector are:
1-2 2.7 volt
3 0volt
4-6 3.3 volt
but pc wont start with battery only.
ordered same battery model code, but that one is a bit larger (same code different type)

edit: im trying with the other battery, as it has same working method. i'll post results here

2.48 volt i assume because rtc battery is a bit low, but some rtx battery have 2.5 or 3 volt so 2.48 should be ok...

edit2: tried other battery same result.... voltage pin with battery and psu plugged in:
pin 1- 2.7 volt
pin 2 3.7 volt
pin 3 0 volt
pin 4-5 3.3 volt

without psu all pins 0 volt...

[mcplslg123]

Re: acer v3-372 dead after battery disconnected

PIN1-2 at 7V seems bit low though there are laptops models with rated battery output of 7.5V-i dont know what is the rated output of your battery but if it is rated anything greater then 11.5V, then your battery is deep discharged and may have entered in protection mode.

[dellxps15]

Re: acer v3-372 dead after battery disconnected

yesterday i did bad measurement. battery pin voltages with also psu connected are:
pin 1-2 2.7 volt
pin 3 2.48 volt
pin 4 0.3 volt
pin 5-6 3.3 volt

battery voltage is 15.2 volt. in windows hwinfo see battery brand, tell me battery voltage is 16 volt, charge level is 0% and wear level is 22%. before all that notebook was working fine with battery only, but 2 keys from keyboard were not working.

tried also the second battery: voltage pins with psu also are:

pin 1-2 2.7 volt
pin 3 4.7 volt
pin 4 is 0 volt
pin 5-6 are 3.3 volt

on windows it see battery brand, tell me battery voltage is 10.5 volt , charge level is 0% and wear level is 8.8%.

this notebook has 2 switch. one is battery reset and one is battery insert. no matter what i press.... results are always the same.

[SMDFlea]

Re: acer v3-372 dead after battery disconnected

check PQ4413

[dellxps15]

Re: acer v3-372 dead after battery disconnected

ok im going to disassemble the mainboard to check it.

is it normal that both battery have 0 volt when not plugged in? if i measure red wire and black wire i have 0 volt... but ofcourse i know they are good....

and what about that 2 cid fuse or temperature sensor i have removed from original battery? can i use battery with 2 wire soldered in it or better get a new one ?



edit: pq4413 not present onboard. all voltages on pins are 0 volt

edit2: i see pq4413 is powered by s0 signal, but laptop with battery only is dead so no power on nothing. it's like i dont have any voltage output from battery.

is there a enable vout for battery when inserted on the computer ?

[dellxps15]

Re: acer v3-372 dead after battery disconnected

tried both battery reset and battery insert button but nothing change

voltage on pq4413 with battery only are 0 volt.

with psu only i see on battery connector pin 1-2 2.7 volt. shouldnt ic generate around 12 volt even when battery is not present ?

tried also with battery only and sometimes it generate 2.7 volt too.... go like 2.7 to 0.5 volt in a loop mode.


edit: measured pin 5 of bq737 and is 0 volt... with psu installed

edit2: measured pr4407 is 14.5k and pr4401 is 31.5k.... im going to replace pr4401 since adapter is 65 watt.

edit3: replaced pr4401 with 100k and when installed is 31.5k . old resistor measured outside the board is 100k too.

[mcplslg123]

Re: acer v3-372 dead after battery disconnected

bq737 pin5 is ACOK#-so it should be low. So nothing wrong there.

[dellxps15]

Re: acer v3-372 dead after battery disconnected

bq737 pin5 is ACOK#-so it should be low. So nothing wrong there.

and what about pin 6 acdet of 2.7 volt ? is that ok?

why battery wont let output voltages?

[SMDFlea]

Re: acer v3-372 dead after battery disconnected

Try another RTC battery its too low at 2.48v .

[dellxps15]

Re: acer v3-372 dead after battery disconnected

rtc battery is 3 volt at source.... somewhere lose that half voltage.

[dellxps15]

Re: acer v3-372 dead after battery disconnected

good morning. today i did some more measurement: with psu only no battery

pu4402 pin 1-4 are 19 volt. pin 5-8 are 2.7 volt.

pu4404 pin 1-4 are 2.7 volt pin 5-8 are 19.5 volt

i think problem is that its not generating 12V_BT+ or that volts comes out only if battery need to be charged ?

with rtc only, no psu and no battery pu4404 pin 5-8 are 0.34 volt....; pq4301 pin 1 is 2.86 volt, pin 2 is 2.6 volt

edit: some other measurement. with battery and psu, pin 3 of battery connector get from 2.48 volt with battery only to 3 with battery+psu also
pin 4 of battery connector pass from 0 volt with battery only to 0.3 volt with battery+psu. with psu only ois 3.2 volt so that should be ok.


edit: ok i measured pin 1-2 of battery with battery only..... 0 volt then i keep measuring while insert psu and i noticed 12 volt coming for 1 second, then drop to 2.7 so i think charging circuit is ok, its just battery not output voltage. kbc or bad battery? with the other battery, on pin 3 of battery connector i have 4.7 volt and all other read are the same


kbc is ene 9028 so its programmable..... maybe it need to be reprogrammed ?

[dellxps15]

Re: acer v3-372 dead after battery disconnected

problem found: button battery-insert had to be pressed with the bottom cover case. after that pc charge the battery. now the original battery doesnt work but with the second battery it charge it, but battery is too big so im going to take another battery and do some test, but 99% should be ok

[dellxps15]

Re: acer v3-372 dead after battery disconnected

Take a look at SW3 Battery Insert,it should be pressed in when the laptop is assembled.

i thougth u were sayng to press it once u put battery if i keep more attention to your post i would have fixed it so easy

[dellxps15]

Re: acer v3-372 dead after battery disconnected

i have a question: the second battery i got was second hand, but unfortunately it was too big for that notebook. in battery info, on the original one was written output volt is 15.4 volt, but battery reading inside windows was 16.8 volt. the second battery has a rating voltage of 14.4, but after charging it for a while, it has 11.6 volt. is that normal or one lipo cell is dead ? it is a 4 cell so should be almost same as the other, or a bit higher repsect 14.4. i mean if one was rated to be 15.4 and is 16.8 the other should be rated 14.4 and be like 15-16 volt.

so in it ok or maybe it's going to die soon ?