Results 1 to 9 of 9
  1. #1
    ROG Member Array
    Join Date
    Mar 2019
    Reputation
    10
    Posts
    5

    Asus rog g751jl won't detect power supply

    My Asus rog g751jl stopped detecting the charger, the led light on the laptop doesnt turn on and the battery is not getting charged, tested the charger and its giving the right voltage, this happen after cleaning the dust on the fans, what could be the problem? Everything else is working fine, it just wont dettect the charger.

  2. #2
    ROG Guru: Orange Belt Array
    Join Date
    Nov 2012
    Reputation
    55
    Posts
    482

    Does the LED on the charger go out when you plug in the laptop?

    First reset the charger, unplug the charger from the wall and the laptop, wait a few seconds, plug the charger back into the wall, check to confirm the charger LED is lit, then plug the charger into the laptop, does the charger LED stay lit?

    If the charger LED goes out when plugged into the laptop then you have a short circuit in the laptop. The most likely cause is the charging circuit on the motherboard. Take it to a technician for confirmation.

  3. #3
    ROG Member Array
    Join Date
    Mar 2019
    Reputation
    10
    Posts
    5

    Quote Originally Posted by jdfrench3 View Post
    Does the LED on the charger go out when you plug in the laptop?

    First reset the charger, unplug the charger from the wall and the laptop, wait a few seconds, plug the charger back into the wall, check to confirm the charger LED is lit, then plug the charger into the laptop, does the charger LED stay lit?

    If the charger LED goes out when plugged into the laptop then you have a short circuit in the laptop. The most likely cause is the charging circuit on the motherboard. Take it to a technician for confirmation.
    The charger doesn't have a led indicator, but its temperature has remained the same since i reseted it and left it plug. If it was the charging circuit could it be repaired?

  4. #4
    ROG Guru: Orange Belt Array
    Join Date
    Nov 2012
    Reputation
    55
    Posts
    482

    I don't know of an ASUS charging brick without a LED indicator. Is yours an aftermarket model? How do you confirm it's operability? Are you using a voltmeter to confirm voltage after unplugging the charger from the laptop?


    Replacing the motherboard would be cheaper.
    Last edited by jdfrench3; 03-24-2019 at 04:38 PM.

  5. #5
    ROG Member Array
    Join Date
    Mar 2019
    Reputation
    10
    Posts
    5

    Quote Originally Posted by jdfrench3 View Post
    I don't know of an ASUS charging brick without a LED indicator. Is yours an aftermarket model? How do you confirm it's operability? Are you using a voltmeter to confirm voltage after unplugging the charger from the laptop?


    Replacing the motherboard would be cheaper.
    http://imgur.com/gallery/EVz4mOH

    This is the charger, its the one that came with the laptop, i tested it with a voltmeter and it was outputting 19.5v.

  6. #6
    ROG Guru: Orange Belt Array
    Join Date
    Nov 2012
    Reputation
    55
    Posts
    482

    OK then:

    Reset the charger by removing it from both the laptop and the wall, wait a few seconds, plug the charger back into the wall, check with voltmeter the charger output, if good then proceed, now while charger is still plugged into the wall, plug it into the laptop, turn on the laptop, let it boot up, now with laptop still running unplug the charger from the laptop, check with voltmeter the charger output, if good then the charger is probably working correctly. It also is a good sign that the charging circuit on your motherboard is not shorted but has an open circuit instead. The LED on the charger acts with an overload circuit in the charger. The LED is lit when it is charging but will go out when an overload current is detected. Checking the charger's output current is preferred to checking only it's voltage.

    I would first suspect the DC Input jack on the side of the laptop. The jack is attached to a small sub board that is then attached to the motherboard. Have you any issues connecting the charger plug to this jack? Look down into the jack with a flashlight there should be a single prong in the middle and the outer edge should be metal. All surfaces should be free of defects.

    Asus G751JL DCIN BD.
    Part Number 90NB0890-R13000
    $26.58

    Replacing this little sub board requires the disassemble of the laptop.

  7. #7
    ROG Member Array
    Join Date
    Mar 2019
    Reputation
    10
    Posts
    5

    Quote Originally Posted by jdfrench3 View Post
    OK then:

    Reset the charger by removing it from both the laptop and the wall, wait a few seconds, plug the charger back into the wall, check with voltmeter the charger output, if good then proceed, now while charger is still plugged into the wall, plug it into the laptop, turn on the laptop, let it boot up, now with laptop still running unplug the charger from the laptop, check with voltmeter the charger output, if good then the charger is probably working correctly. It also is a good sign that the charging circuit on your motherboard is not shorted but has an open circuit instead. The LED on the charger acts with an overload circuit in the charger. The LED is lit when it is charging but will go out when an overload current is detected. Checking the charger's output current is preferred to checking only it's voltage.

    I would first suspect the DC Input jack on the side of the laptop. The jack is attached to a small sub board that is then attached to the motherboard. Have you any issues connecting the charger plug to this jack? Look down into the jack with a flashlight there should be a single prong in the middle and the outer edge should be metal. All surfaces should be free of defects.

    Asus G751JL DCIN BD.
    Part Number 90NB0890-R13000
    $26.58

    Replacing this little sub board requires the disassemble of the laptop.
    URL="http://imgur.com/gallery/f3qoIzb"]http://imgur.com/gallery/f3qoIzb[/URL]

    This is how the dc input jack is looking, y decided to remove the keyboard and test the pins on the piece, on the top left side its still transmiting the voltage of 19v correctly when tested with a voltmeter, i tested the pins on the battery conector and when the battery is disconnected its only getting 1.5v tho.

  8. #8
    ROG Guru: Orange Belt Array
    Join Date
    Nov 2012
    Reputation
    55
    Posts
    482

    I'm guessing your charging circuit on the motherboard is bad.

    Purchase used motherboard and replace.

    Would be a good time to replace your battery as well.

    Good Luck
    Last edited by jdfrench3; 03-25-2019 at 07:13 PM.

  9. #9
    ROG Member Array
    Join Date
    Mar 2019
    Reputation
    10
    Posts
    5

    If anyone encounters this same problem, it seems to be that while cleaning the fans an static shock busted one of the transistors, so be careful when cleaning your computers if you do it by yourself and always wear anti static gear.

    Component 4983NF
    http://imgur.com/gallery/GczjHJr
    Last edited by Crozznova; 03-30-2019 at 01:30 AM. Reason: Album added.

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •