T43 hangs/can't boot when using power adapter, OK with batt

[spintop]

My T43 is facing some issue recently.

- Laptop works perfectly using the battery alone.
- When used with the power adapter with or w/o batt, it failed to boot some times. If it did boot to Windows, it will hang after awhile.
- The batt can charge when inserted into the laptop.
- F2 fuse is OK

Suspect issue with the MOSFET, but not too sure.
Seek some advice here.

[systemBuilder]

I had a problem with a virus recently, and had some of these symptoms. The laptop behaved dead and would only boot from the battery, or not at all, I cannot remember which. I unplugged all power sources for 10+ seconds, and this fixed the problem and it would boot again. However, after about 2-3 mins in the OS, the system would freeze (no response from keyboard, CRTL-ALT-DEL, no response to power button held down 5 secs!) which required unplugging everything, once again!

My point is, keep trying, as the problem you are having could be a software problem - not a hardware problem. Reset the BIOS to default settings towards this end. I solved my problem by uninstalling a bunch of utilities and by running Malwarebytes to get rid of the conduit virus. The machine works as good as new now. I am still using Windows-XP.

[spintop]

mine is actually a hardware problem. its resolve now.
Found resistor and capacitor faulty, replaced them and its working great now on Win 8.
Thanks !

[moebiius]

specs on the resistor and capacitor you replaced? Location? thanks Spintop!

Ken

[spintop]

specs on the resistor and capacitor you replaced? Location? thanks Spintop!

Ken

resistor is 2.2 ohm. surface mount capacitor has no marking which i replaced with a similarly looking one and size from an old circuit board. location near fan.

Hope this helps !!!

[moebiius]

Good sir, by location I meant to say which number location of the smd of the main board, not "near the fan" lmao

Ken

[spintop]

Good sir, by location I meant to say which number location of the smd of the main board, not "near the fan" lmao

Ken

There is no marking or labels for the components.
I noticed many passive components have no proper labels.

[moebiius]

please tell me you have pictures? if not can you specify more in detail what those smd's look like? color? thanks
any help would be appreciated

Ken

[spintop]

please tell me you have pictures? if not can you specify more in detail what those smd's look like? color? thanks
any help would be appreciated

Ken

no photo unfortunately.
smd cap and resistors are all over the place on the board.
maybe u can start looking and testing for open/shorted components near the fan as mention before.
Its a tedious process but that is what i did to resolve by laptop