Troubleshooting hardware from a technician's perspective.

REVISION 2

TABLE OF CONTENTS: 

1. No power
2. No post
3. Vertical lines in your display or dead pixels "dots on the screen"
4. Display slowly fades into white when powering up
5. Screen is white without fading in and out.
6. Display is flickering.
7. Haze/smokey looking discolored area's
8. Display is flickering and the lines appear on and off going horizontal
9. You can see your display but there is no backlight or its very dark
10. Freezes at the bios logo/manufacturer logo
11. Freezes at the bios logo/manufacturer logo, you can see options
12. Hangs at windows progress bar screen
13. System is freezing up within windows
14. System is hanging up or pausing within windows
15. New dvd drive is not recognizing/loading media
16. Wireless does not find any access points
17. Wireless runs slow
18. Beeps when you turn on your unit
19. When your boot to windows you get a green/orange display.
20. Can't connect to lan
21. No sound from speakers
22. External display is not working
23. Touchpad/mouse is not working.
24. Blue screen of death or error codes on boot 0x000000f(or others)
25. Battery light on laptop LED flashing or not working.
26. Battery is not charging.
27. Bios password.
28. Blank screen directly after manufacturer logo on boot. 

Introduction:

Alright, I will revise this document a few times before I leave it be. While looking around Google and other places
I have found that there is not much information about troubleshooting your PC/Laptop. Most places want to charge you money before that give you any information that might save you a buck or two. First off I will introduce myself. I am the admin of this site; Toshiba technician; Programmer; Ex - black hat hacker; the list goes on. My hardware ability is far less honed than that of other area's that I have gained experience in over the years, but I am considered a rather well technician and usually out preform most of the people that I work with. I repair on a daily basis aprox anywhere from 10 to 20 units in a 8-9 hour shift which includes ordering parts, paperwork, tech & diag. I tech and diag 20 units a day within a hour and a half with 90% - 95% accuracy. This isn't a talk about me how to by far. I just want you to have a little faith and believe that I know what I'm speaking on. This article is not going to be a manual to being your own technician so dont take everything I say to heart. This is how I do it. Also just a note: this is mainly for repairing Laptops but you can take some of the information and diag your PC also; so here goes. 

The first thing you should know before you attempt anything that is when dealing with computers and hardware the best way to pinpoint your problem is by trial and error. Usually when I get a unit at work I will approach it according to the problem that I am faced with appropriately. Basically if your having a blue screen within Windows, your not going to jump in and say that the system board is the culprit and start from there. I work down like this, once again depending on the situation...

Memory->Hard drive->System board/VGA board->CPU

Video problems:

Memory->LCD cable->LCD->System board/VGA board

Overheating / Spontaneous shutdown:

Fan->Heatsink->CPU->System board

If you notice you will find that the system board is at the end of the list generally. Even after that comes the CPU. The CPU is a rather dependable piece of hardware that is tested thoroughly and to be honest with you 90% of the time it is not your problem. 

We'll work our way up through the problems that you might usually be faced with. First off....

1. No Power:

No power is a relativly easy problem to diagnose. If you find that you have no LED lights at all! then this is what I'm calling NO POWER. If you have LED lights then your problem is not NO POWER. A no power diagnosis consist of three things. First check your AC adapter/Power cord. This is most likely your problem however if it is not unfortunatly the second most frequent NO POWER problem is the System board. The smart thing to do if you don't have the cash availiable to throw away or the parts on hand would be to try the third option secondly. The third option being your DC-IN cable. This is the cable that your AC adapter plugs into when connecting it to your unit. This cable does go bad so there is a good chance that could be your problem.  

So once again from most likely to least likely:

AC Adapter->System Board->DC-IN cable

2. No POST:

First post is. "POWER ON SELF TEST"

When I say No POST, I'm basically saying that you have LED lights, power/battery/ac and possibly the hard drive activity LED flashing a couple times. However you have no Display or another way to put it your screen is black and the unit acts like nothing is happening. What you need to do if your facing this problem is first off the way I like to do it seeming it only takes a second and you'll eliminate a lot of things at once is to remove your: Memory sticks aka DIMM's, remove your hard drive, optical drive aka DVD-ROM, battery "I've seen it be the culprit". Once you have removed all of these items you need to place one stick of memory back into the proper slot on the system board. If you aren't using the right slot you will notice when you go to power your unit up and it flashes a orange color on the led or just powers back off completly. If this happens put the memory in one of your other slots. Each time you put the one stick of memory in, test it by plugging the AC adapter back in and powering on your unit. If you still have no display then try the other stick of memory if you have one or if not get one that is a known good stick and try it. After trying memory and you still have no display and all the things I said to remove previously are still removed then your problem is one of three things going in order from most likely to least likely.

System board->CPU->Color LCD module "LCD DISPLAY SCREEN"

If you want to test to make sure it is not your LCD you can eliminate it quickly by plugging in a external monitor "If you have video then it is your LCD or LCD cable". This is probably not the problem. When a LCD goes out it starts with dead pixels on the screen or vertical lines. When a LCD cable goes out it usually has a process it goes through also.

In this situation when you have limited yourself to the System board or the CPU you are better off to just go buy a System board. One out of 30-60 units with the No POST problem in my experience has been related to the system board after all the other things "memory,optical drive, hard drive" have been eliminated.

NOTE: if you have had your unit apart recently or had it worked on take out your CPU and hold it up in front of your face in the light. If you see that the CPU pins are not one behind the other in a straight line and one is bent just a bit it will keep it from POST'ing.

If you removed all of the things mentioned before and you now have display then you start putting them back in one by one and powering the unit back on each time until it doesnt have display anymore. When it doesn't have display the thing you placed back into your unit last is the culprit of your problems. Even a DVD-ROM aka Optical drive will keep a unit from POST'ing and seeming that you dont have a display or external video you can not run diagnostic tests to pinpoint your problems.

3. Vertical lines in your display or dead pixels "dots on the screen".

If you are having vertical lines in your display with no other interference or shades of color then your problem is simply your display aka LCD.

4. Display slowly fades into white when powering up

This boils down to the LCD cable or the System board. You can do a few different things to figure this out or possibly even fix it without having to spend a dime. First off to figure out if it's your LCD cable or System board, hook up your external display. If the external display is fine then your problem resides in the LCD cable. If your external display is distorted also then your problem is your System board. 

5. The screen is white without fading in and out. 

Simply remove the LCD bottom cover "Actually named bottom but its the top piece of plastic on your laptop. Usually has the logo of the company who produced the unit on it". Once you've removed the LCD bottom cover by first removing the Bezel "trim around LCD" and whatever else might be in your way on your specific model; look behind the LCD and you will notice a cable which I have been to refering to as the LCD harness or LCD cable; will be running up the back of the LCD and plugging into it. This cable is typically about 2 inches wide and very thin. Disconnect the cable and then reconnect it or simply look to see if it was seated in the first place properly into the plugin. This will almost always fix this problem. 

TIP: Another trick of finding out what the culprit of a display problem is - bend or press around the cable area. By the power button of your laptop or the top of your keyboard, press but not to hard to break anything or gently twist your LCD at your own risk to see if the movement solves the problem. If you have the systemboard in view and the unit somewhat apart "Remember static electricity" You can press on the system board around the LCD harness plugin and often see a change if its the System board "Not always".

 6. Display is flickering.

If your display is flickering your problem is either Memory or the LCD cable. First run a Memtest diagnostic to check to see if you have a bad memory dimm. If you pass the test then plug the external display in and the rule goes like before: If it's fine in external then its your cable. If not its your board. CMI has been producing alot of "defective" LCD cables. If you see that your cable is  a CMI cable you might get a replacement from the company.

7. Haze/Smokey looking discolored area's. 

LCD is the most likely in this situation. Follow the procedure for checking display problems like mentioned before.... Use external; if its still distorted its your board if not its your cable or LCD. Replaced whats cheapest first seeming the cable probably runs about 15$ and the LCD definatly alot more. 

7. Display is flickering and the lines appear on and off going horizontal. 

Alway's been memory with my experiences. 

8. You can see your display but there is no backlight or its very dark.

In this situation you want to first check external. Follow the procedure for troubleshooting display as mentioned above. This one can be kind of tricky because the levels of darkness is usually what I base my judgement on. If it is really dark then your problem is most likely the FL INVERTER. That is a piece of hardware at the bottom of your LCD under the bezel. I understand that if you dont see it everyday you might not know what is considered dark, but you'll have to use your best judgement. If its not as dark I would try the LCD. In this situation your problem could be:

You can eliminate the System board by using external video to test.

9. Freezes at the BIOS logo/Manufacturer logo.

If you do not see the options at the bottom of your screen to hit F12/F2/ESC whichever pertains to your unit, then your problem is most likely the System board. This situation is best approached by disconnecting each piece of hardware and re-powering on your unit to see if it progresses. When it progresses the last thing you disconnected is your problem.

Switch memory->Remove: DVD Drive->Battery->Hard drive->Disconnect keyboard->Touchpad cable->Just to be certain disconnect your speaker cables also. Better safe than sorry. If something is shorting out wierd things can happen.

10. Freezes at BIOS logo/Manufacturer logo, you can see the options.

Once again disconnect the things mentioned above. This could be your CPU if you have disconnected everything and have the System board running with the DC-IN plugged in so you can power it up and the LCD cable plugged in so you can see whats going on.

TIP: A power button board can do funky things also. If you want to see if thats your problem remove your keyboard; disconnect the power button board and switch board "Feather key buttons" and take a flathead screw driver. Touch the sodre points on the opposing site of the System board plugin slot for the power button board. Scrap it across this spot a couple times and you will power on your unit.

11. Hangs at Windows progress bar screen.

This is most likely your hard drive. You can run diag if you made it this far so get a Seagate preferably hard drive diagnostic's tool onto a USB or CD then boot it by hitting F12 to select boot options. Run diag on your memory to just to be safe and if neither is the culprit start unplugging things that would be initiated/loaded at that point. Keyboard/Mouse/DVD/Speakers. If nothing works then re-image the unit's operating system. If you get a error when re-imaging the error will most likely tell you what is wrong by giving you a system error code. Google this error code followed by the name of the operating system. For example FC-0006C Vista. Just an example.

12. System is freezing up within Windows. 

First thing I would try is to re-image the hard drive's operating system. If this does not help your problem and you haven't got any errors by now I would run diagnostic on the hard drive/CPU/memory. The problem will most likely be solved by replacing your System board or Hard drive. 

13. System is hanging up or pausing within Windows. 

This is a hard drive, memory, CPU problem. Run diag on those items and if re-imaging the operating system didnt help then try first by replacing the Hard drive. That will usually solve the problem if not CPU would be the next thing I would tackle. 

14. New DVD drive is not recognizing/loading media. 

Open device manager under control panel and goto the properties of the device. Make sure the driver is installed and working properly. Make sure that the media present is not scratched beyond playability. If you are using a old Vista image and you put a new DVD in then you will need to delete registery keys for the old one using regedit. Google how to do this I will not go into that. Make sure you set the region for your DVD player, it will prompt you if this is the problem and walk you through. Very simple. 

15. Wireless does not find any access points

Control panel then goto device manager. Make sure the driver is installed and working properly. Make sure there is no conflicting software. Sometimes certain router software that you install or even some default Vista images come with software that takes priority over the default wireless tool that handles this stuff. If you can't google and figure it out by using what I told you then your problem is your Wifi card. Before you replace the Wifi card disassemble the laptop and make sure that your wires are not smashed on your wifi card. 

16. Wireless runs slow. 

Doubtful but from a technicians perspective, check your wires that are connected to your wifi card. If your unit was repaired recently or before then the last technician might not had known that if you hook the wires up backwards the wifi card will work but will process things slower. From left to right with the card facing you it should go Black->Grey->White. Depending on if you have a Grey wire and if you dont then of course you got two connection options and it goes Black->White. I'm not going to touch this area anymore this could be many different things from Botnet's and ViRii or just a crappy router.

17. Beeps when you turn on your unit. 

Disconnect your keyboard. If that solves it, your keyboard is the problem. 

18. When you boot to Windows you get a green/orange display.

Replace your hard drive.

19. Can't connect to LAN. 

This is another area I'm not going to walk you through to much. There are many things that fall under this category and yeah I know most people will probably land right here because they can't set up a router or their provider is having issues so they think its hardware. From a tech's perspective: check your memory. If you have Samsung memory try sticking a Hynix for example or possibly others in the Samsungs place removing the Samsung completly. If this works you can do a tricky process to fix it. 

Flash BIOS with a older BIOS.

Place Hynix memory into slot and then flash the BIOS to a new BIOS. 

Replace the Samsung and try again.

If you never see anything appear like the LAN is even trying to connect or recognize your hardware "Theres about 4 lines of text that pops up when you boot to LAN" your problem might be Memory/System board/LAN board. Some LAN boards are built into the System board. Do a memtest. Switch the memory out like I said. Flash the BIOS to a older BIOS. Replace the LAN board. Still nothing? Replace the System board. 

20. No sound from speakers. 

Okay instead of touch base on every speaker problem since they come in a pair of two most of the time we'll just tell you the rule behind speakers. If you have no sound at all first just try!! JUST TRY! FN button on your keyboard + ESC. Hit it a few different times and test it. Keep messing with it sometimes you can get it to snap back to reality. If that dont work and you have no sound from EITHER speaker the rule of thumb is... speakers usually dont go out both at once. They work on channels and usually one speaker will be staticy or noisey or not work at all. If its just one speaker acting up then the problem is your speaker. If both are acting up and the problem appeared suddenly; your problem is your System board. Just keep in mind: If its one its speakers; If its both its the board.

21. External Display is not working. 

Use FN + F5. Do this a couple times while external is plugged in. If you never get anything make sure the cable is plugged into your system board. If it still dont work remove the cable and make sure its not damaged and you can't easily see the damage. Most likely if all else fails that your System board is bad or damaged. The External cable + Connection end doesn't usually go bad.

22. Touchpad/Mouse is not working

FN + F9 . Do this a couple times. Don't just stop if you do it once and nothing happens. You should see enable/disable popup in Vista. If you do this over and over and nothing works then remove the keyboard make sure the touchpad cable is plugged in. If it is then make sure that the connector "silver/sodre looking points" is facing opposite of the plastic locker that is on the plugin where the touchpad ffc cable goes into the system board. This is another tricky problem but if you get a diag tool for your mouse and it says device is not connected then its your touchpad cable ffc. If it says something else its probably your touchpad board. 

Most likely to least likely:

FN + F9->Touchpad cable FFC->Touchpad Board->Touchpad Wide->System board.

23. Blue screen of death or Error codes on Boot. 0x000000f (Or others).

0x000000f can often be recovered using your install cd's that were provided with your unit. If the recovery is not possible you will get another error when recovering which will be the error code you need to google. Provided this error code you will find out what is causing the problem so its a win win situation. 

If you get a blue screen, reboot your computer. When the manufacturer logo pops up hit F8 over and over until a menu pops up. Select disable automatic shutdown on error. Then when you get the blue screen you'll be able to read the problem, write it down, google it and figure out what is wrong. The majority of the error codes are documented for your convienince by microsoft. These blue screens are OS dependant and you will not find them for example on Linux or other Operating Systems. 

24. Battery light on laptop LED flashing or not working.

Either the LED is dead, the battery isnt being detected or the first thing to do is update your BIOS. This is a issue alert on some units. Once updating BIOS this will most likely fix this problem.

25. Battery is not charging.

If the battery is not charging and your positive your AC adapter is good then your System board is the culprit. 

26. Spontaneous shutdown ( Shuts down randomly )

When you power your unit up take your hand and put it beside the fan port. If you feel the fan (might have to give it a second fans arent meant to be running 24/7) , but if you feel the fan going then your problem is probably CPU or System Board. Run a CPU test and if the unit passes the test and doesn't shut off before you complete it then replace the System board. If the fan is not working replace the fan. If the fan is running constantly and doesnt ever shut off try to put some CPU glu on the CPU and on the heat sink in the proper area. If that doesn't help which it probably wont then replace the heat sink. These last few sentences were if your fan keeps running 24/7 keep in mind. 

27. BIOS password.

Send me 500$ and be ashamed at the torment that you will cause me to fix this. :) sorry. haha.

 NOTE: REMOVE YOUR HARD DRIVE FIRST. NEWER MODELS WILL PLACE A HARD DRIVE PASSWORD IF YOU DONT REMOVE THE HARD DRIVE FIRST. THEN YOU WILL BE BUYING A NEW HARD DRIVE AS I DO NOT KNOW A WAY TO CLEAR A HARD DRIVE PASSWORD.

 If you remove the Memory most of the times, or under the keyboard you will find a jumper. Sometimes it is marked with XXX or they will be diamond shaped and kinda ugly compared to the other soder's. There will either be one jumper or two and you will need to take a pair of tweezers or a flathead screwdriver and short the soder's out with the power to your unit off. While holding the jumper with the tweezers/screw driver reach up and power on the unit. If it doesnt go past BIOS password then push a little harder or make sure your points are being connected by the tool your using to do it. "Tweezers/Flathead". Keep trying you'll get it. If you google you could probably find a image of what I'm talking about that you need to jump. Atleast now you know its not hopeless.

28. Blank screen directly after Manufacturer logo on boot. 

Conclusion:

Alright. I'll leave it at that for now. There's tons of stuff I have not touched base on. I'm full of information but lack of sleep has got the best of me. If you have something in preticular that I havent remembered as I did this all off the top of my head without organization; email it to me at This e-mail address is being protected from spambots. You need JavaScript enabled to view it . I'll try to come back once or twice more and revise this document because I believe it to be one of the better technician troubleshooting guides out there that you can get for free.

DO NOT COPY OR REUSE THIS DOCUMENT I WILL SEARCH AND IF I FIND IT I'LL BE MAKING MONEY OFF YOU. I DO NOT WANT THIS DOCUMENT RE-DISTRIBUTED!

Anyways. Thanks alot and hope you appreciate my site and this document.

 - pr4nq /aka ALLTATDUP /mailto: This e-mail address is being protected from spambots. You need JavaScript enabled to view it /web: www.legitcode.com