Badcaps.net Forum
Go Back   Badcaps Forums > Troubleshooting Hardware & Devices and Electronics Theory > Troubleshooting Laptops, Portable, and Mobile Devices
Register FAQ Calendar Search Today's Posts Mark Forums Read

 
Thread Tools Display Modes
Old 12-04-2018, 07:57 PM   #1
Weelcup
TopTech
 
Join Date: Oct 2017
City & State: Manchester
My Country: UK
I'm a: Hobbyist Tech
Posts: 100
Default Need a professional help! Acer E5 does not Power on!

Hi
I have an acer aspire E5-575 laptop the is not responding to power button at all.
I have changed the KBC with new one but still same.
+3VPCU, +5VPCU... are present.. no short or hot component on board.

S5_ON signal is missing. which according to the schematics should come as soon as the power button is pressed.

I have programmed the bios …. no change
I have programmed the KBC … no change.

one thing I noticed recently is that when I remove the bios chip and connect the board to power supply, I get the S5_ON signal but also the board is not powering up and there is no power consume on the power supply.

I replaced the bios chip and reprogrammed it but no luck
I have replaced the TPS51225 that generates +3VPCU, +5VPCU but no luck.
I have replace the charging chip … because I noticed that the motherboard I identify the battery but is not charging it. however it seems that the battery was faulty.

I really get annoyed. this is the most difficult problem to identify I ever used to work on. and I will appreciate any advice.

this is its schematics.
Weelcup is offline   Reply With Quote
Old 12-05-2018, 02:38 AM   #2
MJ-meo-dmt
Senior Member
 
Join Date: May 2016
City & State: East Town
My Country: South Africa
Line Voltage: 220/230VAC 50Hz
I'm a: Professional Tech
Posts: 146
Default Re: Need a professional help! Acer E5 does not Power on!

Is the power button actually working? Is there voltage at the power button? Is the signal going to the EC?
__________________
while alive { live(toFullest=true) }
MJ-meo-dmt is offline   Reply With Quote
Old 12-05-2018, 03:49 AM   #3
piernov
Badcaps Veteran
 
Join Date: Jan 2016
City & State: Valbonne, 06
My Country: France
I'm a: Knowledge Seeker
Posts: 891
Default Re: Need a professional help! Acer E5 does not Power on!

IT8987E has integrated ROM. May or may not be reprogrammed automatically from BIOS if blank on first power on.
If you have an EC programmer flash it manually.
When on AC adapter usually S5 rails are present without pressing power button. Not sure here since it's not written in the schematics.

Check all the power rails going to the EC.
Check the EC reset line WRST# , it's delayed from +3V_LDO_EC so make sure the components are good.

Also check if S5_ON is at least slightly pulsing when plugging in AC adapter.
__________________
OpenBoardview http://openboardview.org | IRC #openboardview@irc.freenode.net
piernov is offline   Reply With Quote
Old 12-05-2018, 01:19 PM   #4
khaahk
Badcaps Veteran
 
Join Date: Dec 2013
City & State: Tallinn
My Country: Estonia
I'm a: Knowledge Seeker
Posts: 531
Default Re: Need a professional help! Acer E5 does not Power on!

Also might be good to check S5_on resistance to gnd. It may be pulled low by any of the lines it is connected to. (alathough if it is high when no bios chip present it should not be the case)
Check #lid signal on ec.
Check for Y2 clock 32khz presence.
Where did you get the ec dump to program? Did you save the old one? Are they same?
khaahk is offline   Reply With Quote
Old 12-05-2018, 11:08 PM   #5
Weelcup
TopTech
 
Join Date: Oct 2017
City & State: Manchester
My Country: UK
I'm a: Hobbyist Tech
Posts: 100
Default Re: Need a professional help! Acer E5 does not Power on!

Quote:
Originally Posted by MJ-meo-dmt View Post
Is the power button actually working? Is there voltage at the power button? Is the signal going to the EC?
Apologies for being late.
Yes there is 3.18v at the power button. And I tested the power button. The power button is fully working but nothing happen when pressed.
Weelcup is offline   Reply With Quote
Old 12-05-2018, 11:15 PM   #6
Weelcup
TopTech
 
Join Date: Oct 2017
City & State: Manchester
My Country: UK
I'm a: Hobbyist Tech
Posts: 100
Default Re: Need a professional help! Acer E5 does not Power on!

Quote:
Originally Posted by piernov View Post
IT8987E has integrated ROM. May or may not be reprogrammed automatically from BIOS if blank on first power on.
If you have an EC programmer flash it manually.
When on AC adapter usually S5 rails are present without pressing power button. Not sure here since it's not written in the schematics.

Check all the power rails going to the EC.
Check the EC reset line WRST# , it's delayed from +3V_LDO_EC so make sure the components are good.

Also check if S5_ON is at least slightly pulsing when plugging in AC adapter.
Thanks for the reply.
Yes there is a plus at s5 pin when ac is plugged.
If I am not mistaken, the schematic referING to s5_on signal to be present in step 8 just after the power button (step 7 )... but I am not sure I'd it refers to pressed power button.
I will check WRST# Signal and come back to you today...

Thanks a lot.
Weelcup is offline   Reply With Quote
Old 12-05-2018, 11:23 PM   #7
Weelcup
TopTech
 
Join Date: Oct 2017
City & State: Manchester
My Country: UK
I'm a: Hobbyist Tech
Posts: 100
Default Re: Need a professional help! Acer E5 does not Power on!

Quote:
Originally Posted by khaahk View Post
Also might be good to check S5_on resistance to gnd. It may be pulled low by any of the lines it is connected to. (alathough if it is high when no bios chip present it should not be the case)
Check #lid signal on ec.
Check for Y2 clock 32khz presence.
Where did you get the ec dump to program? Did you save the old one? Are they same?
Thanks for the reply...
I have my dumped EC and bios.
I also download a dumped EC and Bios online. They doest match exactly but they are for the same board.
I don't know if this make sense but I could only read the ec chip when the bios chip is attached to the board .. even though all the voltage are present in the ec chip.
Weelcup is offline   Reply With Quote
Old 12-06-2018, 11:01 AM   #8
ktmmotocross
Boardkiller
 
ktmmotocross's Avatar
 
Join Date: Feb 2014
City & State: slovakia
My Country: slovakia
Line Voltage: 230VAC 50Hz
I'm a: Hobbyist Tech
Posts: 1,138
Default Re: Need a professional help! Acer E5 does not Power on!

Quote:
Originally Posted by Weelcup View Post
Apologies for being late.
Yes there is 3.18v at the power button. And I tested the power button. The power button is fully working but nothing happen when pressed.
fully working means that he shorted that line when u press it?
ktmmotocross is offline   Reply With Quote
Old 12-06-2018, 11:25 AM   #9
on/off
Member
 
Join Date: Oct 2016
City & State: Forbidden
My Country: Indonesia
Line Voltage: 220VAC 50Hz
I'm a: Knowledge Seeker
Posts: 53
Default Re: Need a professional help! Acer E5 does not Power on!

Also make sure there R741 and have good value resistant.
on/off is offline   Reply With Quote
Old 12-06-2018, 12:58 PM   #10
Weelcup
TopTech
 
Join Date: Oct 2017
City & State: Manchester
My Country: UK
I'm a: Hobbyist Tech
Posts: 100
Default Re: Need a professional help! Acer E5 does not Power on!

Quote:
Originally Posted by ktmmotocross View Post
fully working means that he shorted that line when u press it?
yes that is exactly what I meant...
Weelcup is offline   Reply With Quote
Old 12-06-2018, 01:11 PM   #11
Weelcup
TopTech
 
Join Date: Oct 2017
City & State: Manchester
My Country: UK
I'm a: Hobbyist Tech
Posts: 100
Default Re: Need a professional help! Acer E5 does not Power on!

Quote:
Originally Posted by khaahk View Post
Also might be good to check S5_on resistance to gnd. It may be pulled low by any of the lines it is connected to. (alathough if it is high when no bios chip present it should not be the case)
Check #lid signal on ec.
Check for Y2 clock 32khz presence.
Where did you get the ec dump to program? Did you save the old one? Are they same?
hi again,
I don't have the oscilloscope to test for the 32khz. but on the multimeter hz=50hz... I don't know if that helps..

however, I only get 3mv on LID# on both sides of R260.
the S5 resistance to grd = 40K. so no short.
Weelcup is offline   Reply With Quote
Old 12-06-2018, 01:14 PM   #12
Weelcup
TopTech
 
Join Date: Oct 2017
City & State: Manchester
My Country: UK
I'm a: Hobbyist Tech
Posts: 100
Default Re: Need a professional help! Acer E5 does not Power on!

Quote:
Originally Posted by on/off View Post
also make sure there r741 and have good value resistant.
r471 = 9.83k
Weelcup is offline   Reply With Quote
Old 12-06-2018, 01:41 PM   #13
khaahk
Badcaps Veteran
 
Join Date: Dec 2013
City & State: Tallinn
My Country: Estonia
I'm a: Knowledge Seeker
Posts: 531
Default Re: Need a professional help! Acer E5 does not Power on!

Quote:
Originally Posted by Weelcup View Post
however, I only get 3mv on LID# on both sides of R260.
Lid should be high, that might be your problem.
However it is unclear how it is pulled high, there is a mention about internal pullup (from EC), so is R53 present?
LID# resistance to gnd?
khaahk is offline   Reply With Quote
Old 12-06-2018, 02:04 PM   #14
ktmmotocross
Boardkiller
 
ktmmotocross's Avatar
 
Join Date: Feb 2014
City & State: slovakia
My Country: slovakia
Line Voltage: 230VAC 50Hz
I'm a: Hobbyist Tech
Posts: 1,138
Default Re: Need a professional help! Acer E5 does not Power on!

on power switch should be 3.3V
ktmmotocross is offline   Reply With Quote
Old 12-06-2018, 06:47 PM   #15
Weelcup
TopTech
 
Join Date: Oct 2017
City & State: Manchester
My Country: UK
I'm a: Hobbyist Tech
Posts: 100
Default Re: Need a professional help! Acer E5 does not Power on!

Quote:
Originally Posted by ktmmotocross View Post
on power switch should be 3.3V
the switch is ok and it does short the 3.3v to grd when pressed.
Weelcup is offline   Reply With Quote
Old 12-06-2018, 07:04 PM   #16
Weelcup
TopTech
 
Join Date: Oct 2017
City & State: Manchester
My Country: UK
I'm a: Hobbyist Tech
Posts: 100
Default Re: Need a professional help! Acer E5 does not Power on!

Quote:
Originally Posted by khaahk View Post
Lid should be high, that might be your problem.
However it is unclear how it is pulled high, there is a mention about internal pullup (from EC), so is R53 present?
LID# resistance to gnd?
R53 is not present. I mean the resistor itself is not soldered to the board.
BL# is 3.3v but BL_ON is 0v...

LID# to GND is 6.7M.... no short at all


just 2 questions...
1- now I have 3.3v on the MR1 pin1 but I don't have output at pin2! is that OK?...
2- also SYS_SHDN# is high 3.3v shouldn't that be 0v in order for the system to power up?



thanks

Last edited by Weelcup; 12-06-2018 at 07:17 PM..
Weelcup is offline   Reply With Quote
Old 12-06-2018, 11:28 PM   #17
on/off
Member
 
Join Date: Oct 2016
City & State: Forbidden
My Country: Indonesia
Line Voltage: 220VAC 50Hz
I'm a: Knowledge Seeker
Posts: 53
Default Re: Need a professional help! Acer E5 does not Power on!

Quote:
Originally Posted by Weelcup View Post

just 2 questions...
1- now I have 3.3v on the MR1 pin1 but I don't have output at pin2! is that OK?...
2- also SYS_SHDN# is high 3.3v shouldn't that be 0v in order for the system to power up?



thanks
1. So MR1 need to replace, input present but no output.
2. in old schematics of quanta should be approx 5V-6V (usually getting from resistor divider from VIN). but for this series i think is fine, since you have NBSWON# signal.

AH9249NTR

Last edited by on/off; 12-06-2018 at 11:30 PM..
on/off is offline   Reply With Quote
Old 12-07-2018, 05:25 PM   #18
Weelcup
TopTech
 
Join Date: Oct 2017
City & State: Manchester
My Country: UK
I'm a: Hobbyist Tech
Posts: 100
Default Re: Need a professional help! Acer E5 does not Power on!

Quote:
Originally Posted by on/off View Post
1. So MR1 need to replace, input present but no output.
2. in old schematics of quanta should be approx 5V-6V (usually getting from resistor divider from VIN). but for this series i think is fine, since you have NBSWON# signal.

AH9249NTR
this was a precious reply. thanks a lot. at least we found a faulty element which is mr1... I don't have its replacement are there any alternatives. I am not good at finding alternatives ...
Weelcup is offline   Reply With Quote
Old 12-07-2018, 08:51 PM   #19
Weelcup
TopTech
 
Join Date: Oct 2017
City & State: Manchester
My Country: UK
I'm a: Hobbyist Tech
Posts: 100
Default Re: Need a professional help! Acer E5 does not Power on!

Quote:
Originally Posted by on/off View Post
1. So MR1 need to replace, input present but no output.
2. in old schematics of quanta should be approx 5V-6V (usually getting from resistor divider from VIN). but for this series i think is fine, since you have NBSWON# signal.

AH9249NTR
Quote:
Originally Posted by khaahk View Post
Lid should be high, that might be your problem.
However it is unclear how it is pulled high, there is a mention about internal pullup (from EC), so is R53 present?
LID# resistance to gnd?
khaahk & on/off you both guys were right. I shorted mr1 source and gate pins and olaaaa I have a fully working laptop...

I just need to order AH9249 from china and be patient until receive it. and off course replace its main battery as it. the battery cells are ok but it does have a faulty battery board. it might be the cause to brick MR1 but not sure.

However, all the thanks to you guys who advised me until we get it fixed.. thanks a 100000000000000000000 million
Weelcup is offline   Reply With Quote
Old 12-07-2018, 09:28 PM   #20
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 34,304
Default Re: Need a professional help! Acer E5 does not Power on!

So is MR1 AH9249?
__________________
Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956

Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999

Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl

Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/

TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
budm is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



Badcaps.net Technical Forums 2003 - 2018
Powered by vBulletin ®
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
All times are GMT -6. The time now is 01:20 AM.

Did you find this forum helpful?