Thinkpad X31 - Won't boot unless plugged into the mains...

[streetster]

Hey Guys,

I've got an odd situation with an X31 laptop i've just picked up...

If it's not plugged into the mains, the 'on' button has no effect - the laptop is stone dead... plug into mains, turn on, everything perfect.

So i tried a different battery (from an X30, but still compatible), and the same problem occurs, the laptop seems to be completely dead, but if you plug it into a/c it boots perfectly...


I've had a quick google but not turned up anything, i've tried clearing cmos/etc to no avail... just wondered if anyone had any ideas, or had a similar experience (and hopefully solution!)



Right.. so once it's turned on (ie POST'd) you can unplug the a/c supply and it works fine... why?!

[peterb]

I am assuning that the battery you are testing it with is a good one that has full voltage on the output and is a fully compatible version.. If not then that would be the first thing to check.

If that is so (and this is only a theory) possibly an internal power supply problem with the battery monitoring and charging area. The on/off switch is a 'soft' switch so if there is a problem with the circuitry associated with the battery, it could prevent it from poering up. Plugging in the mains adaptor circumvents that aspect of the start up - but once started the battery will run it successfully.

If that is the case, I'm not sure that there is much you can do to fix it.

[streetster]

I am assuning that the battery you are testing it with is a good one that has full voltage on the output and is a fully compatible version.. If not then that would be the first thing to check.

The X30/X31/X32 laptops all share the same common battery... my X31 battery worked perfectly in the X30 i tried it in...

If that is so (and this is only a theory) possibly an internal power supply problem with the battery monitoring and charging area. The on/off switch is a 'soft' switch so if there is a problem with the circuitry associated with the battery, it could prevent it from poering up. Plugging in the mains adaptor circumvents that aspect of the start up - but once started the battery will run it successfully.

If that is the case, I'm not sure that there is much you can do to fix it.

doesn't sound so hopeful may have a fiddle about inside if i can, see if anything is damaged/amiss...