Thinkpads Forum

I usually run my 770 with the battery partially ejected (but in the holder), so it'll run on AC only and not needlessly put wear on the battery. Once last night, and just now (a few minutes ago), the unit unexpectedly dropped into hibernation and wouldn't power back on again (for more than a few seconds) until I put the battery back in fully. Unit works fine now (LCD isn't showing any battery draw), so I can't understand what's going on.

EDIT: just did it again with the battery installed! I disabled hibernation to see that does anything

Anyone ever seen this kind of problem and know what might be causing it (charging/power circuit problem manifesting itself?)

Ok, this has become more serious...an hour ago it shut down and pretty much refused to power back up altogether (came on for a few seconds then shut right back off). I took the CMOS battery out, tested it (2.8V) and reseated it. Got the unit to come back on again (reset time/date screen), fixed that, and restarted it to where I have XP booted up again (finally). Never had this kind of problem before so I don't know what the heck is going on.

Since I don't think that's the end of my problems, does anyone have any suggestions where the real problem(s) might lie? Both the power battery and AC adapter are good, so I'm assuming it's the unit itself. Can the CMOS battery cause this kind of problem of intermittent flakiness? DC-DC card, perhaps?

If you are sure that your CMOS battery is good, try making sure (when the unit is off) that the hard drive, CD or other removable drive and RAM are all clean and relatively dust free and firmly seated. Also can try going into BIOS settings, going to configuration and selecting "Initialize" to reset any settings that may have gone out of whack.

So far, it seems to be working "normally" again, but I'm going to get another CMOS battery tomorrow when I'm out just to be on the safe side.

Good idea, those things, when they die, can cause anything to happen. In fact, I probably need to get one soon since my laptop's been forgetting the time and date alot lately.

I changed the battery and it seems to be working ok right now, but I'm still not sold that it was the root of the problem. When I changed the battery, it took a good 4-5 tries to get the computer to power up (would keep coming on for a few seconds then shutting down), and the power management is still acting screwy (sometimes the lid switch works, sometimes it works...but the computer comes back on again).

Assuming the problem is still evident, what's the next likely cause of it?

How well did you check the AC adapter?

A few months back, I thought something was wrong with my 600, as it was incorrectly detecting battery/AC power status, despite having the power brick connected.

A month or two later, I was shifting the power brick around and heard a popping sound, but noticed nothing odd on the computer.

Then last Friday evening, I was plugging in the power brick to charge up my battery when I saw a spark by the brick itself. After unplugging it from the wall (hadn't plugged it into the computer yet), I looked over the corde between the brick and the outlet and discovered exposed/damaged wires at the brick end. The strain relief had been broken since I bought the computer used, and I had apparently wound the thing too tightly around the brick too many times. Five bucks at the local computer shop the next day, and I was back in business.

As to repeating the symptoms with the battery in, having the AC adapter connected to the computer may be enough to prevent it from switching to the battery if the brick stops providing power.

Just out of curiosity, how did you determine the AC Adapter to be good?

Rob

But apparently there's still a gremlin at work on my 770X. After my replacing the CMOS battery a couple of months ago and running my TP on an "ice blanket" (one of those things you put in a cooler) for a few days, the problem seemed to go away....until yesterday when some manifestation of it came back. Now on occasion, Windows (XP) will unexpectedly pop up the "Do you want to shut off/standby/restart" box. Happened at least a half dozen times yesterday and already it's happened a few times today. No idea what the problem is this time, but I turned the machine off, unplugged and removed everything removable (HD, PCMCIA card, etc.) and used my can of air (duster) on everything I had access to. Put everything back together and so far, everything's OK, but I'm not holding my breath.

Another question--awhile back, somebody posted a problem with their 600 where the display would stop working if the LCD (top) were set at the 'wrong' angle and only by moving it a couple of degrees either way could they get it to work. The suggestion was that either the connector(s) were loose or the cable itself was bad in one spot. I have a similar problem with my 770 (display blanks once in awhile and either tapping on it or repositioning it "fixes" it) and am wondering...if the cable in mine is going bad, could it be causing all these power management issues with my computer (as well as the display issues)?