Laptop repair

A friend of mine gave me his laptop to repair. Said it wouldn't start...I hit the power button and it started right up and booted into windows...he was perplexed and said it wouldn't do that last week. So I move on to the next problem...wireless network no longer working. I insert the 802.11b PCMCIA card into the slot and it goes in so far almost the entire antenna is inside the laptop. The laptop immediately turns itself off, and refuses to start again. At this point I realize that he left his wireless card in it while traveling and it received a pretty solid blow, shoving the card inside and busting up the internal mechanism. Of course he claims to know nothing about it.

So today I dismembered the laptop and as suspected, the PCMCIA socket is completely hosed. That's fine...if I can get the laptop going again, he can get a usb wireless adapter. I also see a bit more serious problem. When the socket got destroyed, it sheered a diode (I think...I'm not an EE) almost completely off the mainboard. I saw that it was crooked and gently touched it to see if it was loose and it immediately fell off. I'd like to replace it to see if I can't get the thing to boot again. I'm optimistic that it will since it booted before right before I figured out the socket issue. Fortunately, all of the pads are intact. Unfortunately one of the arms broke off the component.

I was wondering if any of you electronic gurus could help me figure out what I need to replace it. All I know about it is that it is marked D3 on the mainboard and that the marking on the component says 62Z. Thanks.

keep track of which way around the diode was mounted.. hopefully it is also silk-screened on the board.

I'd like to replace it to see if I can't get the thing to boot again.

Are you sure that it won't boot with the diode missing anyway? It's a bit risky, but my old webserver ran fine with a couple of capacitors stripped off near the USB ports. I didn't use the USB, so I didn't care...

keep track of which way around the diode was mounted.. hopefully it is also silk-screened on the board.

From looking around, it appears to be SOT-23 package. Anyway it has three "legs", so it can only go one direction. Also, there is an identical one right next to it.

Considering the marking and that's it a diode, it's quite likely that it's a 6.2V zener diode. Links shows a different type package though.

/Michael

It looks like it may be a Hitachi HZU6.2z zener diode. I'll wait on one of you EE guys to confirm.

Edit: Nope...that's not it. Although, it too carries the 62Z marking.

Considering the marking and that's it a diode

Actually, I'm not sure it's even a diode...that was my best guess. I really know next to nothing about electronics.

Anyway it has three "legs", so it can only go one direction.

Seagoon: Funny, that's the first time I've seen a diode with three legs...

TF Eccles: Hey, I keep falling over!

Peter

Might be a HZM62ZMWA which comes in a MPAK package (which according to the package crossreference table looks to be what Hitachi calls the SOT-23...)

/Michael

From looking around on the net that would be my best guess too. That component is supposed to have a marking of 62N though.

Is there any way to test it and see what it is?

A multimeter with diode tester might be able to give you a reading of the zener voltage
(use a needle to get to the broken off leg?). You get a lower (probably around .6 - .7 volt) reading in the forward direction, but should get around the zener voltage in teh reverse direction.

All multimeters with diode test might not go as high as 6.2V - you might rig someting up with a battery/power supply and a series resistor and the diode. With a power supply > 6.2V and the diode in the reverse direction you should be able to get a voltage reading across the diode close to the zener voltage. Use a resistor high enough that the current is kept low enough not to cook the diode...

/Michael

hmm...right....so let a professional handle it?

Maybe I should send it to Stu and see what he can do with it.

Laptop should be shipping out to Stu today. I'll post back here when/if he can fix it.

If the "diode" traces lead to the busted pc-card cage, forget about it. The cage is gone and the diode has no use any more.

My Neice's laptop fell off the bed onto the wi-fi antenna, busted the cage into many peices. It was a surface mount cage, most of the traces were lifted when the pins tore loose. After cleaning out all the loose bits. It booted fine.

The only problem is, its one of those small Sony jobs where the cdrom is external and interfaces via the pc-card.