Solved! HP pavilion 15 black screen

[Stanrfc]

I have hp pavilion 15ab117na.Getting black screen when power on.No beeps no lights no HDD light.When I remove RAM I get beep code and lights.I read 3:2 lights and 3 beeps.Nothing corresponds to this code with HP.I tried different RAM but can't guarantee it (ebay) but still same.I tried good HDD still nothing and no HDD light.Is the problem motherboard or graphics chip?

 

[BEAUFORD_SAVAGE]

More likely a power supply issue, on the motherboard. Are you running on battery or wall supply?
If you can find a meter, carefully meter the output of the wall supply. It's easy to short the output pins on the power supply connector,
depending on the type connector, which will blow the PS fuse internal to the power block. No risk of shock however.
Write back if you want to follow up on this.

 

[Stanrfc]

More likely a power supply issue, on the motherboard. Are you running on battery or wall supply?
If you can find a meter, carefully meter the output of the wall supply. It's easy to short the output pins on the power supply connector,
depending on the type connector, which will blow the PS fuse internal to the power block. No risk of shock however.
Write back if you want to follow up on this.

Thanks for your response.Could you explain a bit more what I should do and how to rectify.Thank you.

 

[Stanrfc]

Thanks for your response.Could you explain a bit more what I should do and how to rectify.Thank you.

Ps. I have both battery and AC power adapter.

 

[Stanrfc]

More likely a power supply issue, on the motherboard. Are you running on battery or wall supply?
If you can find a meter, carefully meter the output of the wall supply. It's easy to short the output pins on the power supply connector,
depending on the type connector, which will blow the PS fuse internal to the power block. No risk of shock however.
Write back if you want to follow up on this.

I forgot to say in my initial post that the fan runs ok when I hit on button and the optical drive operates too.

 

[BEAUFORD_SAVAGE]

I forgot to say in my initial post that the fan runs ok when I hit on button and the optical drive operates too.

That tells me 1 of three supplys is good. The 12V. (And I assume your power from the wall) There is also the on-board regulation of both 5V and 3.3V.
That narrows it to motherboard. You could open it and trace wires from the power supply input to the motherboard, Where those wires connect, look for swollen capacitors.
It could literally be a less than a dollar part, or 2 parts that just needs replacing, and all goes back to normal. This is a VERY common failure. Examples below.
If a silver cylinder is not COMPLETELY flat on top, It's bad. In the 2nd link, the top looks flat, but you can see goo leaking out the bottom. Thats a 22 Micro-farad 16 Volt capacitor.
This is assuming you want to open it up and do a visual inspection of the Mommy-Board. If you have a meter, see if you can find 5V and 3.3V. This could save you hundreds of $$$.
Reply if you want to proceed, if you can take GOOD close-up pics, I can help further.

https://forums.tomsguide.com/threads/hp-pavilion-15-black-screen.490385/

https://lh6.googleusercontent.com/p...1vbvKDL7QjsvJZ8WoDsObNUp=w1200-h630-p-k-no-nu

 

[BEAUFORD_SAVAGE]

I forgot to say in my initial post that the fan runs ok when I hit on button and the optical drive operates too.

Oh, and remove the battery, just for simplicity of troubleshooting, Just use the wall supply.
Also, I got nothing in your last message but a repeat of what I said.

 

[Stanrfc]

That tells me 1 of three supplys is good. The 12V. (And I assume your power from the wall) There is also the on-board regulation of both 5V and 3.3V.
That narrows it to motherboard. You could open it and trace wires from the power supply input to the motherboard, Where those wires connect, look for swollen capacitors.
It could literally be a less than a dollar part, or 2 parts that just needs replacing, and all goes back to normal. This is a VERY common failure. Examples below.
If a silver cylinder is not COMPLETELY flat on top, It's bad. In the 2nd link, the top looks flat, but you can see goo leaking out the bottom. Thats a 22 Micro-farad 16 Volt capacitor.
This is assuming you want to open it up and do a visual inspection of the Mommy-Board. If you have a meter, see if you can find 5V and 3.3V. This could save you hundreds of $$$.
Reply if you want to proceed, if you can take GOOD close-up pics, I can help further.

https://forums.tomsguide.com/threads/hp-pavilion-15-black-screen.490385/

https://lh6.googleusercontent.com/p...1vbvKDL7QjsvJZ8WoDsObNUp=w1200-h630-p-k-no-nu

I have opened it a few times.Visually I think it looks ok. I'll open it again later.I will try and get some voltages.Trying to figure out how to upload pictures.Do I need to upload them to a third party first?.

 

[Stanrfc]

That tells me 1 of three supplys is good. The 12V. (And I assume your power from the wall) There is also the on-board regulation of both 5V and 3.3V.
That narrows it to motherboard. You could open it and trace wires from the power supply input to the motherboard, Where those wires connect, look for swollen capacitors.
It could literally be a less than a dollar part, or 2 parts that just needs replacing, and all goes back to normal. This is a VERY common failure. Examples below.
If a silver cylinder is not COMPLETELY flat on top, It's bad. In the 2nd link, the top looks flat, but you can see goo leaking out the bottom. Thats a 22 Micro-farad 16 Volt capacitor.
This is assuming you want to open it up and do a visual inspection of the Mommy-Board. If you have a meter, see if you can find 5V and 3.3V. This could save you hundreds of $$$.
Reply if you want to proceed, if you can take GOOD close-up pics, I

https://imgur.com/a/bWP4RFl

I apologise if I'm sending gobbledegook I'm finding it hard to navigate this site . I'm using android phone.This is a pic I took earlier.Not the best but I'll take more.

 

[Stanrfc]

That tells me 1 of three supplys is good. The 12V. (And I assume your power from the wall) There is also the on-board regulation of both 5V and 3.3V.
That narrows it to motherboard. You could open it and trace wires from the power supply input to the motherboard, Where those wires connect, look for swollen capacitors.
It could literally be a less than a dollar part, or 2 parts that just needs replacing, and all goes back to normal. This is a VERY common failure. Examples below.
If a silver cylinder is not COMPLETELY flat on top, It's bad. In the 2nd link, the top looks flat, but you can see goo leaking out the bottom. Thats a 22 Micro-farad 16 Volt capacitor.
This is assuming you want to open it up and do a visual inspection of the Mommy-Board. If you have a meter, see if you can find 5V and 3.3V. This could save you hundreds of $$$.
Reply if you want to proceed, if you can take GOOD close-up pics, I can help further.

https://forums.tomsguide.com/threads/hp-pavilion-15-black-screen.490385/

https://lh6.googleusercontent.com/p...1vbvKDL7QjsvJZ8WoDsObNUp=w1200-h630-p-k-no-nu

https://imgur.com/a/V24mrBh

 

[BEAUFORD_SAVAGE]

You did a good job of pic taking. I wish I could say I saw something wrong.
I agree with you, I see nothing visible. And most time you can see something wrong visually,
unfortunately not always. It's also possible one of the switching regulators has just failed with no
visible failure. Using Imgur is just fine with me BTW.
I think it's time to get a meter. Wherever you see large areas of copper that the negative sides of the
Silver cans, (Electrolytics ) connect to, or the marked side also negative. Find a easy spot to hold your meter negative probe
to, with your left hand, then with your right hand, Assuming you are right handed, move the positive probe around to find the voltages
we know are supposed to be there. We have established +12v is there, now you can check for 5V and 3.3Volt. The fans should be at 12 to 12.5V, If less
than 12V, that could still show a problem.
I saw some capacitors marked with a voltage less than that, probably part of the data buss lines to and from memory
and CPU. DAMN! I really wish we could have found something easy with the electrolytic caps, but I guess that would just be too easy!
I sincerely doubt this has anything to do with the issue, but you can pop out the coin cell battery, if below 3v, it needs replacement.
With batteries 1/2 voltage does not mean 1/2 the life left. It means long since dead.
Do you know anyone you can borrow a meter from, to spare you the cost of buying one? Getting one of your own would be more useful
than you may think though. Start with checking the easy voltages, like the connectors to the DVD, 12V and 5V, and USB connectors have 5V.
Kinda stuck till a meter is in play. I'll give this some more thought as to what else can be checked.

 

[BEAUFORD_SAVAGE]

In this pic,

https://imgur.com/a/riM69Pb

View: https/imgur.com/a/riM69Pb

View: https/imgur.com/a/V24mrBh#L2SOt0l
the cap closest to the CMOS battery should be checked closer.
I have the cap marked as you will see.
You need a perfectly straight piece of metal to set of top of it. Like the sharp side of a utility razor, or Exacto blade.
If it doesn't sit flat on top, but can rock even a little, this could be a bad capacitor. And the others with pink markings by it, would need to be replaced as well.
These are only rated at 2.5 volts, so they are such low energy, I would not expect them to be obviously bad, like the higher voltage/current caps show.
That would be a good place to meter as well. Their voltage should be 1.8Vdc DDR2 or 1.5V FOR DDR3 for the microprocessor and memory parts of the board. The meter will tell the story much better than the visual inspection.

 

[Stanrfc]

In this pic,

https://imgur.com/a/riM69Pb

View: https/imgur.com/a/riM69Pb

View: https/imgur.com/a/V24mrBh#L2SOt0l
the cap closest to the CMOS battery should be checked closer.
I have the cap marked as you will see.
You need a perfectly straight piece of metal to set of top of it. Like the sharp side of a utility razor, or Exacto blade.
If it doesn't sit flat on top, but can rock even a little, this could be a bad capacitor. And the others with pink markings by it, would need to be replaced as well.
These are only rated at 2.5 volts, so they are such low energy, I would not expect them to be obviously bad, like the higher voltage/current caps show.
That would be a good place to meter as well. Their voltage should be 1.8Vdc DDR2 or 1.5V FOR DDR3 for the microprocessor and memory parts of the board. The meter will tell the story much better than the visual inspection.

I do have a multimeter.You have been extremely helpful and appreciate your prompt replies . I'll let you know how I get on.Oh one more thing it couldn't possibly be a bios thing could it.?I downloaded the file but when I ran it and tried to extract to save to flash drive my other laptop froze completely.Its an .exe file.I tried about 5 times with same result.

 

[BEAUFORD_SAVAGE]

OH NO!, Now you have TWO computers down? 😡😵
DO NOT try to change the BIOS!!! The computer is BROKE. This will not go well for you if you try to upgrade the BIOS now! You MUST know the computer is in good enough shape to be able to do this update. And right now is NOT that time!!

 

[BEAUFORD_SAVAGE]

I hope you have a good back-up for that other computer, sounds like you corrupted that C drive, trying to run a BIOS .EXE file for a different computer on it.
SIGHHHHH
When troubleshooting you must stick to one train of thought at a time.
And I will repeat myself, with all the countless computers I have repaired, I have yet to see the BIOS chip go bad. But I have seen several where a BIOS update went bad, and corrupted the data on it. So leave that BIOS chip alone.

 

[Stanrfc]

OH NO!, Now you have TWO computers down? 😡😵
DO NOT try to change the BIOS!!! The computer is BROKE. This will not go well for you if you try to upgrade the BIOS now! You MUST know the computer is in good enough shape to be able to do this update. And right now is NOT that time!!

My good laptop is ok I think.I followed HPs guide to downloading a BIOS update to a flash drive.I didn't run it.Just downloaded it and when prompted to save it to whatever drive I changed to flash drive which caused the freeze.Force closing the laptop and starting it again was ok.
https://support.hp.com/in-en/document/ish_3932413-2337994-16

 

[BEAUFORD_SAVAGE]

My good laptop is ok I think.I followed HPs guide to downloading a BIOS update to a flash drive.I didn't run it.Just downloaded it and when prompted to save it to whatever drive I changed to flash drive which caused the freeze.Force closing the laptop and starting it again was ok.
https://support.hp.com/in-en/document/ish_3932413-2337994-16

Happy to hear that. Now set that aside until you determine if the power supplys are working.