I took a look at a thinkpad T42 that refused to start.
Customer thinks there is something wrong with the power socket in the back of the laptop.
He said the power supply itself is ok, as he did the “tongue test” on the plug… Owww, 16 volts must hurt (I find testing a new 9 volt battery just bearable!).
Anyway, I measure the voltage, and its OK, but the socket at the back feels loose… This is a familiar sight, as sockets often get damaged when people lift up the front of the laptop while the plug is still in the back…
I hope this doesn’t become a solder and pray job… they are often not worth it (as the socket will usually break again in just a few weeks/months)
So I take the laptop back to the office, dismantle it (with the usual array 40 tiny screws, in about 8 different shapes and sizes), and test the power socket. Luckily the socket is not soldered onto the motherboard… it has wires that go to another plug… and that goes into a socket on the motherboard.
Now thats a brilliant idea. The mechanical wear and tear on the main socket is isolated from the motherboard… thus fewer motherboard problems.
Anyway, the socket is kept in place with a screw (which was slightly loose… so I tighten it). I cant see that a holding screw would cause a power problem, so I look around a bit more, but I find no scorch marks, no burnt electronics, nothing unusual.
I’m thinking: if the laptop doesn’t start after I re assemble it, then its an untraceable motherboard fault.
So, after some re assembly, the laptop starts! woohoo!
I try to do some tests, put my cd in the drive, but it doesn’t show up in windows explorer.
Hmmm, I pop the CD out, and… the laptop suddenly restarts… Now thats strange.
I think: I hope I put everything back correctly!
I pull out the CD/DVD drive (luckily it doesn’t need any laptop disassembly!), and inspect it (and the drive bay it came from), but I find nothing unusual.
I power up without the drive, and XP starts normally.
I shutdown, insert the CD drive, restart, and windows starts normally. Explorer shows a CD/DVD drive as usual.
I experiment with opening and closing the tray door, and find it randomly resets the laptop. Sometimes while opening the tray, sometimes while closing the tray. And sometimes the laptop refuses to start until the drive is removed.
The only thing that is consistent, is that the drive will not read a CD.
So I pull out the drive and give the customer his options:
either get a replacement drive (a gcc-4242n drive (fru 13n6769)) is not easy (nor cheap) to find.
Or buy an external usb CD/DVD drive.