Laptop Not Booting After Disassembly to Clean Fan - Codeless Caps Blink w/ F12 Light

[FanAttic]

I have an HP Pavilion laptop, a 2012 Model # dv6-7013cl, approximately 6 years old, and out of warranty since 2014. When turned on, the caps lock flashes continuously - no blink code - and the F12 orange button light stays on. It will not boot or show anything on the screen.

The laptop previously worked without issues other than overheating easily. For this reason, I disassembled it and cleaned the fan. There was a layer of lint inside the fan housing so thick that I at first thought it was a foam filter strip. After removing the lint and cleaning off dust with brushes and ear swabs, I reassembled everything and found the laptop in its current no-boot state.

The fan runs and blows warm air, and at a much better rate since being cleaned. The computer will power on with only the battery, with only the power cord, or both, and the screen flashes for a fraction of a second before going  back to dead black and beginning to flash the caps lock light. I have since disassembled and reassembled the laptop at least four times and left it charging overnight without any change in its condition. I've quadruple-checked for missed connectors, board damage, etc. and found none.

NOTES:

(1) Because the CMOS battery is fit tightly into the laptop's plastic frame, I had to disconnect it in order to remove the motherboard and the fan for cleaning. Thus the BIOS was reset on an old battery.

(2) I initially misseated the memory cards, but found this problem and fixed it before the second reassembly. Reseating the memory cards multiple times has not changed the problem. I used photos prior to disassembly to ensure that they were replaced in their original slots.

(3) I have read through and followed all relevant sections of the HP Support Document "Computer Does Not Start and Emits an LED or Beep Code" found at https://support.hp.com/ph-en/document/c01732674. The caps lock key is NOT blinking a code; it is blinking continuously at a rate of about 1 blink per second.

Besides reseating the memory cards, I've tried the "Hard Reset" described in the HP Support Document. I've also tried the ever harder reset described here on IFixIt: https://www.ifixit.com/Answers/View/19132/Caps+Lock+and+Num+Lock+LEDs+blink+continuously%2C+can%27t+...

(4) I am an about as computer-literate as a person can get without formal training. I respectfully have no interest in paying for HP's out-of-warranty overseas phone support service. I am seeking diagnostic and repair suggestions from people with ideas. I appreciate all help and will follow and report back on any suggestions that are provided.

Thank you!

[Riddle_Decipher]

@FanAttic

Welcome to HP Forums, 

This is a great place to get support, find answers and tips, 

Thank you for posting your query, I'll be more than glad to help you out 🙂 

As I understand device isn't booting into windows anymore and has a blinking caps-lock,

Don't worry as I'll be glad to help, however, to provide an accurate resolution, I need a few more details: 

Did you go through the list of caps-lock blinks that defines 1 blink per second or less continuously?

If you've missed on that, I must let you know that it represents a - "CPU not functional" or CPU failure.

That said, you may need to have the CPU / Motherboard in case the CPU Slot is faulty,

There are two ways of doing this, since you need ideas on fixing it on your own:

You could purchase the part from HP, use the HP Parts surfer to identify the part: Click here & order it via the HP Parts store (Click here) or alternatively, Contact HP for setting up an order/service via phone support and it doesn't necessarily take you to overseas support, so you can try your luck!

HP Support can be reached by clicking on the following link:  

* Open link:  www.hp.com/contacthp/

* Enter Product number or select to auto detect

* Scroll down to "Still need help? Complete the form to select your contact options"

* Scroll down and click on HP contact options - click on Get a Case & phone number.

They will be happy to assist you immediately. 

If the unit is under warranty repair services under the manufacturer's warranty will be free of charge.

If you would like to thank me for my efforts to help you, 

feel free to give me a virtual high-five by clicking the 'Thumbs Up' icon below, 

Followed by clicking on the "Accept as solution".

Have a great day!

[FanAttic]

@Riddle_Decipher


Thank you for your reply!

I did not see the part of the Support Document which defines 1 bink per second or less.  I see that a one-blink code is the CPU, but I did not see anything defining a constant blink.  Is that in another support document, or does it fall under the one-blink code?

In any case, it sounds like I probably have an issue with my CPU.  Perhaps this occurred when I removed the fan's heat sink from the CPU?  I see that the thermal paste, which appears to be silver-based, has leaked onto some of the external components.  Perhaps this, combined with whatever jostling occurred during the heatsink removal, caused the CPU failure.  Since I can't update the BIOS prior to replacement, I will plan on replacing it with an identical AMD A6-4400M.

I'm also concerned about a metal Z-shaped spring  that's making contact with the copper heatsink tube near the fan.  I didn't notice if this spring was insulated from the copper tube or not by some foam tape that I had to remove to disassemble and clean the fan.   Do you think it could have caused a short circuit?  I have no idea if this spring carries an electrical current or not, and am worried it might short a replacement CPU.

Here are some pictures for illustration:

[Riddle_Decipher]

@FanAttic

Thank you for replying with this detailed response 😉 

I appreciate your time and efforts,

You've assumed it correctly, the one blink is the same as 1 blink per second or less.

That said, if you've replaced parts on your own and feel that somewhere around the course of replacements it has caused an issue with the short circuit, you may want to Contact HP to have the device either repaired or replacement as advised earlier as there's little to nothing I can do to fix such issues.

I wish there was more I could do to help, however, according to what you've described so far, it's possible the short circuit is the cause of the failure and I'm at the end of the line as there's nothing else I can suggest but to Contact HP for further assistance.

If you would like to thank me for my efforts to help you, 

 feel free to give me a virtual high-five by clicking the 'Thumbs Up' icon below, 

Followed by clicking on the "Accept as solution" button.

Have a great day!