Sony Vaio blinking LED codes?

Hi everyone, I've already Googled for a good while about this, and can't seem to find any information.

I have a ~5 year old Sony Vaio laptop (model# VGN-FE670G) that has worked fine, minus a few hiccups, since I bought it new. These hiccups were, the hard drive has failed on it twice (it's gotten 2 new hard drives in its life... last one was less than a year ago), and the touchpad buttons don't work very well (solved by simply using a wireless USB mouse). The only other thing I've done to it is add some RAM, for a total of 1.5GB (it came with 512MB, I added a 1GB Kingston stick). I have Windows 7 x32 installed on it.

It hasn't had constant use until the last 6 months or so, and since it started being used most of every day, I added a cooling fan pad under it.

Anyway, here's the issue... a few days ago, when powering it on, the two power LEDs (green) and the battery LED (yellow) all blink in unison, constantly. The BIOS has no diagnostics built into it. I've gotten it to boot into Windows, but it won't stay powered on long... and when it shuts off, it acts as if it just lost power -- a completely hard shutdown. All three LEDs blink from the moment it is powered on, until it shuts itself off.

I'm guessing there's something wrong with the motherboard, but I don't want to fork over $100 for a working one (or more for a new one) if I can fix this some other way. The "service manual" for the computer that I found only has disassembly instructions. Does anyone know what these blinking lights mean, or how I can find out? Obviously this thing is WAY out of warranty.

Things I've tried are, the "RAM dance" (trying each RAM chip in each slot, etc.) and removing the battery and power cord and holding down the power button to drain the CMOS battery. Neither of these have had any effect. The computer's pretty clean inside, as I'm pretty vigilant with using Dust-Off on my computers.

Any help would be much appreciated.

 

I'm guessing the battery can no longer hold a charge.
Remove the battery and just use the power plug. Does this eliminate the blinking lights?
If so, first problem solved.

As far as the power cutting out, it might be overheating. You said it was clean inside but are you sure the fans work? If a fan isn't working, it would shut down to protect the CPU.

 

Well, I'm slightly embarrassed... I didn't even think to check if it could be an issue with the battery. The battery (which I forgot to mention) is an aftermarket replacement that doesn't have the charge information circuitry built into it, and contrary to what I know is best for it, the machine remains plugged in most of the time and the battery stays in the machine all the time.

I just removed the battery and am using the power cord only, and the blinking lights went away... so thank you very much for that tip! I was really hoping against having to replace the dang motherboard.

I really don't think the issue is heat, but I'll check the temperatures on the machine with Everest to be sure. It wouldn't be the first laptop I've completely disassembled to remove dust that can't be gotten to any other way. You're right, that is something that can be caused by overheating, but it coincided with the blinking lights... which is why I thought they were connected (and I still think that is possible).

 

Well, something is definitely strange... after booting it without the battery present, I tried putting the battery back in to reproduce the blinking LED lights... and now the computer acts as it did before it started its shenanigans.

Battery in, power cord plugged into it (and the wall), lights are normal, computer operates normal.

Temps are normal as well... main CPU temp @ 41C, core 1 @ 28C, core 2 @ 26C, HDD @ 30-31C. The motherboard lists @ 2C, so either it doesn't have a sensor, or the sensor is malfunctioning, obviously, since the ambient temperature is ~22C.

I'm going to let this thing run overnight (it's currently almost 1 A.M. here... GMT +1) and make sure the temperatures aren't affecting it. Whether they are or not, I'll probably do a complete disassembly cleaning on it within the next month or so anyhow, since I've never done that with this machine.

I just find this whole thing a little bizarre.

EDIT: Remember, the blinking lights CONTINUED after removing the battery and power cord and holding the power button, then reconnecting the battery and power cord to power the machine back on.

 

I left the computer fully on all night (no programs running), and temps were about the same this morning, and it's still acting just as it did before the blinking lights started.

I moved the computer (powered on, battery in, disconnected the power cord briefly to move it) and no issues there, either.

The only thing I can think of is that powering it on WITHOUT the battery in reset something in the BIOS/CMOS.