Dell laptop diagnostic blink codes?

shamrin

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I've got a Dell Inspiron 1526 with no POST, no screen activity, no disk activity. The dash lights do come on but they stop with the Caps Lock and Num Lock lights blinking fast. This can't be good but I can't find anywhere (including the Dell site) that says definitively what this means. Taking out the RAM and/or HDD has no impact on the sequence, so this must be the system board but it would be nice to have an authoritative reference.

Does anyone know or have a link to what these blink codes mean?
 
Have you tried booting without the battery in and just from the power adapter?

Are you holding the Fn key down while pressing the power button (PSA Boot Method) to get the codes?


If you are getting this:
M07%20keyboard%20error%20flash.gif

I think that means a keyboard problem.


If your getting this:
M07%20Video%20error%20flash.gif

I think that means a video error.


If it is a system board I think all three would blink like this:
M07%20motherboard%20flash.gif
 
Have you tried booting without the battery in and just from the power adapter?

Are you holding the Fn key down while pressing the power button (PSA Boot Method) to get the codes?

The first time I tried the FN+ON test the two lights on the right were solid and the one one the left was blinking. Subsequently, I get the first light blinking, the second solid and the third dark. Whatever the FN+ON does, it has made it so the machine doesn't light-up at all with the standard power button. Do you have access to any more of these codes, this is exactly what I was looking for?



The computer needs to POST for the PSA tests to work. All I've got to go on are the blinking keyboard light codes.
 
The first time I tried the FN+ON test the two lights on the right were solid and the one one the left was blinking. Subsequently, I get the first light blinking, the second solid and the third dark. Whatever the FN+ON does, it has made it so the machine doesn't light-up at all with the standard power button. Do you have access to any more of these codes, this is exactly what I was looking for?

The PSA (Fn key + power button) alternate boot method forces a thorough POST test, which provides a more accurate lock LED no POST code.


The LED's are Num lock - Caps Lock - Scroll Lock They may appear different on your model than in any of the pictures below.
I_port_LEDs_pm_1a.jpg



Bay Wolf
http://www.bay-wolf.com/portpostcodes.htm
FLASHING - ON - ON = CPU (Reseat or replace) or system board.


FLASHING - ON - OFF = I don't have a clue.
You may want to search the Dell community web site
http://en.community.dell.com/search/SearchResults.aspx?q=led+lock+codes


Dell Solution Network: Step-by-Step Troubleshooting Wizard:
This is the only LED codes the wizard tells about your model
ON - FLASHING - FLASHING = No memory in system error code.
ON - FLASHING - ON = memory error code.
FLASHING - FLASHING - ON = video error code.
FLASHING - ON - FLASHING = LCD error code.
 
Well, as it turns out I fixed the problem by changing the CMOS battery (which requires a complete disassembly of the computer - nice design Dell).

How does a dead CMOS battery manage to completely disable a machine? This is something to bear in mind with these popular Dell machines, it sure looked for all the world like a system board problem, I was this close to writing it off.
 
Well, as it turns out I fixed the problem by changing the CMOS battery

How does a dead CMOS battery manage to completely disable a machine
Well, was the CMOS battery completely dead or did it still have some charge in it?
How did you get the idea to change the battery?
I would think if the battery was dead you would still be able to POST but all the CMOS data would be lost.
I'm wondering if the CMOS data got corrupt and changing the battery reset the CMOS data.
I'm also wondering if the lock led code FLASHING - ON - OFF means corrupt CMOS data or bad battery.
 
Well, was the CMOS battery completely dead or did it still have some charge in it?
How did you get the idea to change the battery?
I would think if the battery was dead you would still be able to POST but all the CMOS data would be lost.
I'm wondering if the CMOS data got corrupt and changing the battery reset the CMOS data.
I'm also wondering if the lock led code FLASHING - ON - OFF means corrupt CMOS data or bad battery.

These are all good questions for which I can find no real documented information. The battery is rated 3V and measures 1.8V so it's on its last leg. I completely agree that it makes no sense that a low voltage on the CMOS battery would prevent the computer from booting. A more logical explanation is that a low voltage battery corrupts CMOS and there is no way to clear it short of removing the battery. This amounts to a distinction without a difference as the fix is the same either way.

The idea of changing the battery came to me from The Google as I was trying to find an explanation for the blink codes. I came across this guy who seemed to have the same symptoms and fixed it with a battery change. I don't charge customers for handing them back a dead computer and so neither I nor the customer had anything to lose by swapping the battery.

IMO, the blink codes are useless because Dell apparently chooses not to publish them. Or possibly they are objectively useless because they are undependable. The only thing I am sure of is that making the operation of a laptop utterly dependent on the operation of a button-battery is questionable design.
 
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