USB not functioning even though it has voltage

[ktm_kannan]

hi all
i have a Laptop Sahara AL096 Image Book series (PL5C)
it has a Hannstar JMV4 motherboard ATI Xpress 200m Chipset.
In Linux the motherboard is listed as ATI Bonefish.. (can't make it out)

some time ago the laptop suddenly died for few days (it won't switch on and all the lights will light up.) then it became alright but one of the USB ports was not functioning (one of the two in card). (total 3 ports 1 one the MB and other two as a separate card.)

recently the same thing happened. now another port got damaged. this time the port was on the MB itself.

now i became curious and i used a USB charging cable to check whether it has Power. surprisingly both the damaged ports showed power. now sometime one of the damaged port may work but only for few minutes.

now it is very difficult to operate on single USB...

can this problem be diagnosed in any way.?? is there a way out of it??

 

[acer0169]

Have you ever put a friend USB flash stick into the ports?

I've gone through whole USB hubs by putting a knackered USB stick into each port - each time breaking the port for good. If I put something like a USB Wireless adapter in there you can see it's getting power.. but nothing shows on the computer.

Have you managed to break the ports with a broken USB device?

 

[ktm_kannan]

i have used only my portable HDD and USB flash drives (and of course mouse). all these devices are detecting and working fine on other machines.

as i said the devices may detect for sometime at random.. on one of the port the last port is ok

 

[acer0169]

Does it show in device manager as anything out of the ordinary? Like instead of saying Generic USB Hub or something, it says unknown device or has a yellow ! on it?

 

[ktm_kannan]

no in the device manager the usual USB items are there including Enhanced USB Hub for 2.0
now another funny thing is happening. when all the 3 ports are not detecting i will just reboot the laptop (switch off wait few sces then turn it on), one port will function. (others don't function whatever i do.) now this may be a problem with OS. but same thing happens with Linux and Windows.

i am at a loss.

one of my friend is suggesting that i should try "Hot Air" on the motherboard to check if there are any dry soldering.. is it good? will it cause any damage?