Toshiba laptop continuing problems model A205-S5804.

I'm reminded of the joke about the patient raising an arm above his head and saying "It hurts when I do that, doctor!"

"Well, don't do that!"

Obviously you can't run the computer solely on battery power.

Can you get ahold of a new power supply? It's possible the supply you have is noisy, or generates a transient when plugged into the computer.

Have you cleaned out the cpu heatsink fins or is the cpu fan not working? The cpu runs faster when plugged into power and might be overheating. Chuck

When I had it apart to reset the Eprom the fan and heat sink looked pretty clean. I think I'll look at the power supply output on the scope and while observing it I'll load it and see if anything happens. If you guys have any more ideas though, I'm all ears. Lenny.

My wife's Dell laptop was acting flaky when run on AC. LEDs flashing randomly and refusal to boot up. Sometimes it would boot up and then lock up. I traced it to the power supply. There are three wires in the power supply cable. Of the three two are of a heavier gauge than the third. One of the heavier wires, the braided one that also acts as a shield was soldered badly. All I did was reflow the solder to this wire and the laptop resumed normal operation. Eric

Did you replace the backup battery?

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I didn't because the time and date and all parameters seemed to have stayed up. Lenny

It may be screwed up. For now, to deal with it set the power balance the sa me for AC and battery and see what happens.

Almost all laptops dim the display and change the processor mode from perfo rmance on AC to economy on battery. This is the main thing that could be fr eezing the OS. If it was rebooting, shutting down or something then that wo uld be different. It is looking for a power configuration that is likely no t there.

On mine I can control it from Windows, but not all machines will have that and if you reload or reset stuff, this config data coulld be missing or cor rupt. It can be in BIOS or the OS, or both. (kinda like control panel)

Go back into setup, find power management. If you can find in there ANYWHER E that differentiates between battery power and AC, set them identical. Or turn the whole feature clean off if possible.

Incidentally, before proceeding, will it boot up from AC power ? If so, doe s DISconnecting the AC power cause this as well ? If not, you set everythin g to run as if it on batteries all the time. In fact that is probably best anyway, unless it dims the screen and makes it hard to see. I only run mine on battery in the dark because otherwise it is too hard to see.

Hell, I guess a solar battery for it would just about fix me up woulntit.

same for AC and battery and see what happens.

formance on AC to economy on battery. This is the main thing that could be freezing the OS. If it was rebooting, shutting down or something then that would be different. It is looking for a power configuration that is likely not there.

t and if you reload or reset stuff, this config data coulld be missing or c orrupt. It can be in BIOS or the OS, or both. (kinda like control panel)

ERE that differentiates between battery power and AC, set them identical. O r turn the whole feature clean off if possible.

oes DISconnecting the AC power cause this as well ? If not, you set everyth ing to run as if it on batteries all the time. In fact that is probably bes t anyway, unless it dims the screen and makes it hard to see. I only run mi ne on battery in the dark because otherwise it is too hard to see.

I looked in Bios and can't find anything to do with power management or battery power etc. I don't think it's an option on this version. Could it be called something else? Lenny

e same for AC and battery and see what happens.

erformance on AC to economy on battery. This is the main thing that could b e freezing the OS. If it was rebooting, shutting down or something then tha t would be different. It is looking for a power configuration that is likel y not there.

hat and if you reload or reset stuff, this config data coulld be missing or corrupt. It can be in BIOS or the OS, or both. (kinda like control panel)

WHERE that differentiates between battery power and AC, set them identical. Or turn the whole feature clean off if possible.

does DISconnecting the AC power cause this as well ? If not, you set every thing to run as if it on batteries all the time. In fact that is probably b est anyway, unless it dims the screen and makes it hard to see. I only run mine on battery in the dark because otherwise it is too hard to see.

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BTW this never happens when you disconnect the battery. Only if you connect it while you're using it. Lenny

"BTW this never happens when you disconnect the battery. Only if you connect it while you're using it. Lenny "

AHA ! There are regulators all over the place and most depend on electrolytic capacitors.

See where I am going with this ?

The controls for power management are usually available from the operating system. Which OS does this computer run?

Don't know if this will help, but it's made it possible for me to change power settings in control panel on some laptops.

What version of Windoze does this Toshiblah run? (Basic, Home, Pro, etc)? Looking at the specs, it appears to have come with Vista.

What did you use to reload Windoze? A recovery partition on the hard disk? A Toshiba recovery disk set? A recovery disk set that you created? A retail Windoze CD? A random Windoze CD? It should be something from Toshiba or you're guaranteed to have driver problems.

Oddly, I've had difficulties using the recovery partition on other vendors (HP and Compaq) drives. It installs correctly, but then Microsoft update refuses to update for various reasons. There are plenty of workaround but even after they're applied, the system usually ends up "unstable" or strange. I've had much better luck using the manufacturers recovery CD/DVD sets.

Toshiba uses a two wire power jack scheme, so there's no normally closed connection in the jack. That used to cause such problems on older laptops, but not this one.

When you say plugging in the power supply, does that mean:

1. 117VAC power is applied to the charger, and then plugged into the laptop?
2. Or, power jack is plugged into the laptop and 117VAC is applied? If the latter, I've seen power supplies that belch strange and disgusting waveforms and DC when starting up and that can confuse the laptop power management circuitry. If you have another Toshiba or 19V clone battery charger, try it.

So, it won't restart if the charger is plugged in? I would normally suggest that you try running the laptop with just the charger, and with the battery removed. However, that's risky with a possibly defective charger, so don't try it. Replacement chargers are $8 and up on eBay, so it may pay to just order one and see what happens.

Hmmm... This sounds more like software than hardware. Google for power management registry repair or try Microsoft Fix-It:

Coincidence is a bad substitute for cause and effect. Clearing the password probably has little to do with the power problem UNLESS you did the procedure that requires shorting two pins on the motherboard. One mistake, and poof.

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
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Skype: JeffLiebermann     AE6KS    831-336-2558

This doesn't sound exactly like the problem, but it's a similar issue. I have a Dell with a (formerly) bad battery...long story...the laptop charge light blinks an error sequence. The laptop encourages me to replace the battery by this behavior. The battery will only charge with the computer off. The computer always runs off battery, even when plugged in. The only way to run on AC is to REMOVE the battery. Battery issues can have non-obvious symptoms.

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A few observations and history: Yes I did have to clear the bogus CMOS password problem by shorting the two points on the mother board going by the procedure that you had sent me the link to Jeff. And I never had this "freezing" problem before the password issue. However it's more complicated than that.

Also I did find the power balance information that Jurb suggested. It wasn't in BIOS but in control panel. There were three fields, and I made them all identical but that didn't seem to make a difference. They addressed dimming the panel on battery and two other things.

Further, after clearing the password a few weeks ago, the computer seemed unstable. So we copied a few needed files to a memory stick and my son dumped the hard drive and installed Windows 7 from a disc he had, that among others had an OS version on it for "Toshiba". This computer was given to us so we never had a rescue disk of any kind to go with it, and unfortunately I don't recall what OS was in there before he dumped it. So I don't know when this "freezing" problem actually occurred, after clearing CMOS, or after he installed the new operating system. I also don't know anything about the disc he used, like where it came from or even if it was OEM etc.

Another observation: I always plug the AC in first. Then I connect the

19VDCjack to the computer. If I disconnect the the DC plug it's done with the power supply still connected to 120V as well. The computer will never freeze when disconnecting the DC plug, rather it's only when connecting it to the computer when it's running on battery alone.

This afternoon I looked at the power supply on the scope. This supply is rated 19VDC 3.95A. With no load the output read 19.2V. There was a small 20mv.low frequency triangle waveform present. Approximately every 6 usec. there was a 160mv. spike. I took a better look at the spikes. They actually looked like ringing pulses with a width of about

80 usec. I then loaded the supply with a 4 amp resistive load. The voltage dropped to 18.9V and the spikes increased in amplitude to about .900V. every 6usec.

Now given a SMPS that's charging LI-ion batteries I don't know whether or not the above constitutes a "noisy" supply or if these kind of aberrations are to be expected. So I figured I'd substitute my bench supply with linear regulation as a test.

I set up 19 V with a current limit of 4A. I then connected this to the computer and after hitting power on I immediately noticed the current meter surging to 100ma. every second or so. The computer booted up and worked for about 2 minutes and then just shut down. Afterwards I was not able to get it to come back on with the bench supply. Thinking that trying to use a linear supply to power a device with LI-ion batteries probably wasn't the smartest thing to do I then connected the suspect Toshiba supply and the computer booted up and never froze during a 1 hour period of using it. I'm chasing a ghost.

So now what I do know is that the power supply does spike up to .900V when its fully loaded. I don't know what the actual load of the computer is, and since I couldn't simulate this I figured I'd go for worst case. However I think that I can assume that it must also spike somewhat when connected to an already powered on computer as well. Whether or not it's supposed to do this or if this is my problem is anyone's guess. It's pretty clear that the computer does not like to run on pure DC though. Lenny

Not clear what that means. I've seen universal install disks for XP. They address the OEM activation issues, but probably don't have all the drivers you need for every version of every Toshiba computer ever made.

Assuming you have a quality scope and probes and know what you're doing,

0.9V sounds like a lot, but probably not killer.

I've seen some wacky designs, but never seen a laptop that wouldn't run off a DC bench supply.

Some power supplies are identified by a '1 Wire' device that tells the laptop that it's the right supply. There are three contacts at the output plug.