06-09-2010 09:43 AM - edited 06-11-2010 11:24 PM
My A31 does not start or run from the battery. When I press the power button, I hear a buzz sound. It seems to be louder near the battery, but it may be on the motherboard.
The batter does charge ( indicates will hold about 60% of capacity ) left from the 110 or so cycles. A multitester reading of 11.1V (no load obviously) - I can power a 12V LED strip, but I am afraid to try something more demanding that could blow the battery fuse.
Getting a new battery would determine if the battery is the problem, but it would be a waste if the motherboard is the problem. Given the notebook`s weight, a battery is not absolutely necessary, but practical at times.
Has anyone else had this kind of problem with the A series?
06-22-2010 10:48 AM
According to the service manual on page 40, the battery voltage is fine, so is the resistance between pins 4 and 5. I guess the motherboard is the problem.
Obviously some power does get drawn from the battery to make that sound, but which component is defective is difficult to know with out looking at the board. When I press power, hear the sound, but then plug in the power supply, it starts and works fine. Unplugging with a fully charged battery, the system dies - no sound.
I have no intention to open the system if I do not have the schematic. Getting replacement components is not that difficult. Does anyone have a schematic or any knowledge of this type of problem?
06-23-2010 08:59 PM
ThinkPad schematics are considered proprietary information and not available publicly...
11-08-2010 02:38 PM
The A31 that I am using right now makes the squealing noise, but only when it is charging. It has gotten better though, but it still won't charge when it is off. Does the sound come from the left hand side near the power input? That's where mine does. If I figure it out, well, I'll see what it is.
11-08-2010 07:00 PM
The battery charges and discharges, but I cannot run the computer from the battery.
If the AC is not conneted, when I press the power button, all I hear is high pitch squeal ( I have good hearing).
Check to see if is the power brick or the computer itself. Most AC adapters make a high pitch noise depending on the load.
11-08-2010 10:38 PM
See, mine does the same thing, but I can run it off of the battery. I get about an hour and a half of battery life. but if it runs all the way down, it won't get past the bios screen. It gives me a low battery error, and dies. but in the short time it is on, it will charge. so, to remedy this, I have to take out the hard drive and the cd and floppy drives.